State police in New York's lower Hudson Valley were told by the Middlesex County, N.J., prosecutor that Anthony Trapp was in the area with his children and they searched several local motels before finding his vehicle parked at the Bear Mountain Bridge Motel in the Hudson River hamlet of Fort Montgomery, 45 miles north of New York City.
Police say Trapp's New Jersey plates had been replaced by New York tags.
Troopers set up a perimeter around the motel, and around 7:30 a.m. Friday "by chance the kids walked out" of room No. 3 already fully dressed, said Capt. Joseph Tripodo. Members of the state police special operations team scooped them up, wrapped them in blankets and carried them to safety, he said.
Police then spent more than an hour trying to communicate with Trapp by phone and bullhorn. At 8:40, troopers entered the room and found Trapp dead on a bed, Tripodo said.
New York police weren't saying how he died, but New Jersey authorities later said he apparently killed himself, although details weren't released. An autopsy was planned for later Friday.
The girls were taken to St. Luke's Cornwall Hospital in nearby Newburgh. Officials said they were unharmed. Relatives of the girls' mother were en route to the hospital.
A search for Trapp, 39, and 20-month-old Sophia and 5-year-old Emma began Thursday after the girls' mother, 37-year-old Heather Trapp, was found dead inside his home in Old Bridge, N.J., about 70 miles south of Fort Montgomery.
New Jersey authorities issued an Amber Alert for the couple's children. It was canceled when the girls were found safe.
Douglas and Ingrid Johnson, owners of the five-room Bear Mountain Bridge Motel for more than 40 years, said everything appeared normal when Trapp checked in around 7:30 p.m. Thursday night, paying $85 up front for the room with a double bed and two twin beds. Trapp said he only had one child with him, Douglas Johnson said.
"There was no indication there was any problem," Johnson said. "He seemed calm, there was nothing there that seemed abnormal."
But "everything changed about 4 a.m.," Johnson said.
Police arrived and told the motel's owners they had suspicions about the man in Room No. 3 and that the man's wife had been found dead in New Jersey.
About 40 state troopers, including a dozen special operations officers, converged and began trying to make contact with Trapp, to no avail, Tripodo said.
The girls, with the older one leading the way, came out about 7:30 a.m. and were taken to the Johnson's house on the property.
"We're not sure what the children knew or what they know at this point," Tripodo said.
A neighbor, Sue Castelluccio, was on her way home from her transportation job at the military academy and was not allowed to go up her street. She could hear police trying to contact Trapp by bullhorn.
"Anthony, come out," she remembered police saying. "Anthony, answer your cellphone. You did the right thing by letting the children go."
Daniel Malarkey, who lives across the street from the motel, heard about the police response at a coffee shop, went home and learned about the Amber Alert on television.
"I thought `This guy's holed up right across the street from me,"' he said. "The officers told me to stay inside my house or I might get shot."
Just minutes after the ordeal ended, Ingrid Johnson said it was too overwhelming for her to talk about.
"I don't want to. It's upsetting," she told The Associated Press by telephone. "All I know is the little girls are safe. They're fine."
Two buildings comprise the L-shaped motel. The five rooms are in a one story, whitewashed stucco building with gray trim. On Friday, the door to each room was adorned with a small Christmas wreath. A separate, two-story house is the office and the Johnsons' home.
Police in Old Bridge said Heather Trapp went to her ex-husband's home Thursday to pick up the children after a visit with their father. Later in the evening, a concerned relative of Heather Trapp called police, who went to the home and found her body.
Old Bridge Township resident Anthony Dalessio was close friends with the Trapps, and said he and his wife are devastated by their neighbors' deaths.
"She was one of the best people we ever met. She would do anything for her children," Dalessio said. "Even while they had their problems, her children were her main priority."
He said Anthony Trapp was unemployed, and Heather Trapp worked as a dental hygienist in New York City.
Associated Press writers Wayne Parry in Trenton, N.J., and Chris Carola in Albany contributed to this story.