Police say the driver who struck the brothers is suspected of being under the influence of alcohol at the time of the crash.
READ MORE: Johnny Gaudreau's widow pays tribute to him in social media posts: 'You were perfect'
The Columbus Blue Jackets, as well as New Jersey state troopers, confirmed the passing of the Gaudreau brothers Friday morning.
NHL star Johnny Gaudreau, brother killed by alleged drunk driver in New Jersey
What we know about the crash
The crash happened around 8:30 p.m. on Pennsville Auburn Road (County Route 551) near Stumpy Lane in Oldmans Township.
Johnny, 31, and Matthew, 29, were biking close to the line on the side of the roadway.
Police say 43-year-old Sean M. Higgins, of Woodstown, New Jersey, was traveling north on Pennsville Auburn Road in a Jeep Grand Cherokee when he allegedly attempted to pass a slower-moving sedan and SUV.
Police say Higgins entered the southbound lane of the roadway and passed the sedan.
When he attempted to reenter the northbound lane, police say the SUV in front of him moved into the middle of the roadway, splitting the north and south lanes in order to safely pass two bicyclists on the right side of the road.
Higgins then attempted to pass the SUV on the right and struck the Gaudreau brothers from behind, troopers said.
The Gaudreau brothers died from their injuries, according to state police.
According to the police affidavit, the trooper who arrived on the scene detected a "strong odor of alcohol," and Higgins allegedly told the trooper he had consumed "five to six beers" before the crash.
Higgins allegedly told investigators that he thought the driver of the SUV was trying to stop him from passing. Higgins told investigators that his consumption of alcohol contributed to his impatience and reckless driving, according to the criminal complaint.
The trooper also said Higgins then failed a field sobriety test.
Higgins has been charged with two counts of death by auto, state police said. He is being held at Salem County Correctional Facility, where he will remain until a detention hearing on Sept. 5.
The driver made an initial court appearance via Zoom on Friday. He spoke briefly to say he understood the charges and would be hiring his own attorney.
'Truly two amazing humans'
Johnny Gaudreau leaves behind his wife, Meredith, whom he married in 2021. He was the father of two children, Noa, who was born in September 2022, and Johnny, who was born in February. The couple have been since 2021.
Matthew Gaudreau is survived by his wife, who was pregnant.
The brothers also leave behind their parents and two sisters.
One of their sisters, Katie, was set to be married during a ceremony in New Jersey on Friday, followed by a reception in Philadelphia. Both brothers were listed as groomsmen on her wedding website.
The brothers' uncle wrote in a statement, "Last night we lost two husbands, two fathers, two sons, two brothers, two sons and brothers in law, two uncles, two nephews, two cousins, two family members two teammates, two friends but truly two amazing humans."
Nicknamed "Johnny Hockey" because of his love for the game, Gaudreau was a star at Gloucester Catholic High School in Gloucester, Camden County before becoming an NHL star.
"Johnny and Matt were incredible hockey players and students, but even more amazing human beings," Principal Thomas Iacovone Jr. said in a statement. "Their loss will be felt forever by the entire Gloucester Catholic community and by me personally. I will continue to pray for them and their families during this unimaginable tragedy."
Deputy Oldmans Township Mayor Dean Sparks says Johnny would visit with children at the local elementary school.
"The kids love that stuff. We've never had a famous athlete from Pedricktown, so it's tragic. Words can't describe it," he said, adding that the brothers were a source of pride in the community.
Sean Grevy, the founder of the 43 Oak Foundation, said Johnny was always there to help the organization, which breaks down barriers for intercity, minority and underprivileged hockey players.
"What's important to know about him is that he stepped up to the plate for a lot of charities, including ours, and he was just a charitable guy," said Grevy.
As children, the brothers inspired the younger players in their community, like Colin Felix, who currently plays in the American Hockey League.
"Johnny was a little bit older than me, so was Matty, but those were the kids who were the best players in the area," said Felix.
"I know there are going to be a lot of guys who touch the ice over the next few months, and they're going to be thinking about Johnny, and they're going to play a little bit harder and enjoy that moment on the ice a little bit more" added Grevy.
Memorials continue to grow at the crash site.
"I just wanted to have my presence here. I knew his family. I knew his dad," said Wayne Bumm, of Oldsman Township. "A lot of good hockey players in South Jersey, he was probably the best. That's why he was Johnny Hockey."
Fans laid flowers and hockey sticks for Gaudreau outside Nationwide Arena in downtown Columbus and outside the Flames' home rink in Calgary. Tributes reverberated near and far, with moments of silence occurring in Cincinnati before a Major League Baseball game between the Reds and Brewers and prior to an Olympic qualifying hockey game between Slovakia and Hungary in the Slovakian capital of Bratislava.
Both brothers played hockey at Boston College.
BC called Johnny Gaudreau one of its "greatest" players and "one of the nicest," adding that Matthew Gaudreau also "was a gifted player & beloved by teammates."
"The entire BC community is stunned by the tragic news," BC said in a statement.
After playing for teams in the AHL and ECHL, Matthew returned home to South Jersey, where he served as the head hockey coach at Gloucester Catholic.
"The Gaudreau siblings were proud New Jersey natives," New Jersey Governor Phil Murphy said.
A small memorial comprised of flowers and hockey sticks appeared at the Hollydell Ice Arena in Sewell, New Jersey, where the Gaudreau brothers grew up playing the sport.
Matthew was a junior hockey coach there. Current players with the Philadelphia Rebels said they are still processing the news.
"I just didn't want to believe it. So I just kind of went to bed and woke up and saw the news that it was true and I was shocked," said Brock Jones of Buffalo, New York.
"He was a great guy. He was always willing to bring a guy into his office and talk to him about whatever he wanted to talk about," said Ryan Bunting of West Deptford, N.J. "It hit a lot of guys extra hard because he was more than just a coach and a good player, he was a great guy. We all had really good connections with him."
Hollydell released a statement saying in part, "As the best of local success stories, Matty and Johnny have motivated countless young hockey players in the south Jersey community. While our collective grief will linger for some time, we will continue to celebrate Matty and Johnny at Hollydell Ice Arena."
Johnny went on to play 11 professional seasons, starting his career with the Calgary Flames and most recently playing for the Columbus Blue Jackets.
The Blue Jackets posted to social media, saying the team is "shocked and devastated by this unimaginable tragedy."
Johnny grew up watching the Philadelphia Flyers. In 2014, he got the chance to play at Wells Fargo Center for Boston College in the Frozen Four.
"It's exciting. Never thought I would get the chance to do this, play in front of my hometown friends and family. Playing for the Frozen Four National Championship, it's an exciting year, so far, and my goal, our team goal, has been to get to Philly this year," Johnny told Action News at the time.
A year later, he got to face the Flyers while playing for the Flames. He talked about that experience in the locker room.
"It's you know my dream come true. Growing up watching the Flyers, I always dreamed about playing for the Flyers and playing in the NHL. And it's not the Flyers I'm playing for, but you know, it's an NHL team that gets to play against the team I grew up watching, so it's exciting for me," he said.
The Flyers released a statement on the tragedy, saying, "Johnny and Matthew were deeply rooted in the Philadelphia and New Jersey community, where they spent their entire childhood on the ice... Throughout all of their success in the hockey world, both continued to give back to our community."
"Johnny and Matthew were, and always will be, beloved and cherished members of the Flyers community and entire hockey world," the statement continued.
The National Hockey League also released a statement, saying in part, "While Johnny's infectious spirit for the game and show-stopping skills on the ice earned him the nickname 'Johnny Hockey,' he was more than just a dazzling hockey player; he was a doting father and beloved husband, son, brother and teammate who endeared himself to every person fortunate enough to have crossed his path."
'His talent on the ice was enhanced'
Johnny Gaudreau, at 5-foot-9 and 180 pounds, was part of a generation of hockey players who thrived in an era of speed and skill that made being undersized less of a disadvantage. He scored 20-plus goals six times and was a 115-point player in 2021-22 as a first-time NHL All-Star when he had a career-best 40 goals and 75 assists.
NHLPA executive director Marty Walsh said: "Johnny was a beloved teammate and friend in both Calgary and Columbus, and he was a joy to watch during his 10 years and 763 games in the NHL. ... The players and staff of the NHLPA are devastated by these terrible losses."
A fourth-round pick of Calgary's in 2011, Johnny helped Boston College win the NCAA championship in 2012 and in 2014 took home the Hobey Baker Award as the top college player in the country.
As a professional, Johnny was part of the NHL all-rookie team during his first season in the league and was third in voting for the Calder Trophy as rookie of the year in 2014-15.
He was a point-a-game player with 642 points in 644 regular-season and playoff games since breaking into the league. In 2022, he left the Flames to sign a seven-year contract worth nearly $69 million with the Blue Jackets that put him and his young family in central Ohio, closer to his family in New Jersey.
Social media was full of an outpouring of messages about Gaudreau, from USA Hockey to the Flames and beyond the sport itself.
Longtime executive Brian Burke, who had Johnny in Calgary and with the U.S. national team, said it could not be overstated just what a joy it was to have him around.
"There are few players in hockey history who matched his passion and love for the game of hockey." Burke said. "His talent on the ice was enhanced, not diminished, by the fact that he was having fun out there."
Former Flames teammate Blake Coleman posted that he was "completely gutted. The world just lost one of the best." Retired goaltender Eddie Lack called Gaudreau one of his favorite teammates.
"Always happy, always spreading positivity around him," Lack said. "Rest in Peace my friend and prayers for your wonderful family."
In international play, Gaudreau owns the men's world championship records by a U.S. player with 30 assists and 43 points.
Gaudreau's death is the latest off-ice tragedy to strike the organization in the past few years. Goaltender Matiss Kivlenieks died in July 2021 when he was struck in the chest by a firework while attending the wedding of then-Blue Jackets goaltending coach Manny Legace's daughter in Michigan.
The team is now left to deal with another unexpected loss three weeks before training camps around the league are set to open.
ABC News and The Associated Press contributed to this report