29-year-old Keith Campbell of Bear, Delaware has been charged with three counts of homicide by vehicle, aggravated assault, reckless endangerment and possession of an instrument of crime.
The district attorney's office said the investigation is ongoing and more charges are possible.
Campbell had been previously charged with four counts of 'accident involving death or bodily injury.'
Campbell remains hospitalized in critical condition, suffering from multiple stab wounds that authorities say may have been self-inflicted. A knife was found in his vehicle, police say.
A written note - described by authorities as "rambling" - was found inside Campbell's vehicle. Police have not determined if it was a suicide note.
Police are also looking into whether he was under the influence prior to the crash.
The fatal collision happened around 1:45 a.m. Wednesday at 7th Street and Packer Avenue.
Police say Campbell veered his 2014 Audi A4 into opposing traffic and crashed into a 2015 Acura RDX.
Joseph Ferry, 36, of Philadelphia and his fiancee 35-year-old Kelly Wiseley of Glenolden, Pa. were killed.
The couple had just gotten engaged on Christmas.
Thirty-one-year-old Dennis Palandro of Morton, Pa. was also killed.
His 30-year-old wife, Nicole Palandro, remains hospitalized in critical condition with a broken pelvis.
The two male victims were members of the South Philadelphia String Band. Palandro's father is a captain of the band.
As the Mummers community heard of the tragedy, black bunting was hung at South Philadelphia String Band's clubhouse at 28th and Porter streets.
In a statement late Wednesday morning, the South Philly String Band said:
On behalf of the officers and members of the South Philadelphia String Band, we are deeply saddened at the loss of our family members.
We ask you to keep all families in your thoughts and prayers.
While the Mummers community is a close knit family, we ask for privacy for the families and our organization during this difficult time.
The South Philadelphia String Band family will be making no further comment.
The Palandros' neighbor Sam Kobielink Jr. says his prayers go out to the family.
"There's no good way coming out of this. She's got to wake up and her husband passing," said Kobielink Jr.
Send a News Tip to Action News
Learn More About 6abc Apps