The dead man was identified as Tyrone Moss and the wounded as Joshua Johnson and Lamel Duffy, all in their mid-20s, said Lt. John Godzieba, the township's acting police chief.
Moss, of Fleetwing Drive in Levittown, was found in the Winder Drive house with a gunshot wound to the head, Godzieba said.
Johnson, who lives in the house, was shot in the head, Godzieba said, and was in critical condition on life support Tuesday. Duffy, of Veterans Highway in Levittown, was shot in the back and was in serious condition.
The shootings occurred just before 1 a.m. Tuesday, he said. Police responded after Duffy scrambled to a neighbor's house to call 911 after being shot.
Godzieba said township and county detectives found shell casings, but had not recovered a weapon, had not determined what kind of gun or guns were used, and had not identified any suspects.
While there were no signs of forced entry and little evidence that suggested a struggle, Godzieba added, police were treating the incident as a home invasion.
He would not elaborate, saying only that investigators "processed the scene pretty intensely."
Residents and family members lined the block Tuesday, setting up lawn chairs in front of their modest, single-story homes while waiting to hear from police.
Godzieba said that the Winder Drive area, about a mile from Bucks County Community College's Lower Bucks Campus, is "one of our neighborhoods that has a higher than average crime rate," and that drugs were often openly dealt and used there.
At least three killings have occurred in the Winder Drive area since 2006. Matt Weintraub, Bucks County's assistant district attorney, called that number "extraordinary" compared with the rest of the county, which typically sees five to 10 homicides per year, according to FBI crime statistics.
Before Tuesday, the most-recent killing on Winder Drive was in 2007, when Jimmy Moore, 19, was slain outside his home on the same block as Tuesday's shooting. That crime remains unsolved.
In 2006, Jarrett Osborne, 18, was shot and killed on Winder Drive while running from two armed robbers. David Ramtahal and Nyako Pippen were convicted on murder charges in 2008 after ballistics and DNA tests linked the men to the crime.
Weintraub said anyone with information on Tuesday's shooting may call Bristol Township Police at 215-785-4040.