Bucks County authorities ruled the death of a Levittown blues guitarist and songwriter a homicide Friday.

But two days after Bristol Township police found Daniel DeGennaro, 56, dying from a shotgun wound to the chest near the front door of his Crabtree Drive home, investigators remained tight-lipped regarding any leads they may have.

"We don't believe it was a random attack," said District Attorney David W. Heckler. "But there are a number of avenues of investigation to pursue. We have a number of layers of things to look at."

Investigators returned to DeGennaro's home Friday.

Emergency responders arrived at the house about 10 p.m. Wednesday, after a neighbor called 911 reporting that someone had fallen and was injured.

Nick Wilson, who lives down the street, said he made that call after a tenant living in the guitarist's basement showed up on his doorstep in a panic. The two returned to DeGennaro's house to a gruesome scene.

"The house looked like it was robbed, and someone got hurt really bad," Wilson said.

On Thursday, police interviewed and released the tenant. They do not consider him a suspect at this time, investigators said.

Detectives were spotted removing several firearms from the residence. Authorities said Friday that none was believed to be the weapon used to shoot DeGennaro.

For Bob Settelen, a friend and vice president of the Bucks County Blues Society, nothing about DeGennaro's death makes much sense.

"It's a sin. The guy didn't deserve to go like this," he said. "He was an incredible musician."

Also known as Danny Rio, DeGennaro had toured with Kingfish, a band that counted the former Grateful Dead guitarist Bob Weir among its members. According to his website, he had also performed with Bo Diddley and the late E Street Band saxophonist Clarence Clemons.

A Pennsbury High School graduate, he had recently put his touring career on hold and returned to Levittown to care for his mother, Dolores, who died of cancer in November 2010.

Friends described him as a devoted father to his daughter, Gia Marie - a frequent fixture at Kingfish shows.

"They were really close," said Kevin Kirwan, manager of DeGennaro's latest project, a five-man blues act known as the Danny DeGennaro Band.

The band's members said Friday that they were planning a tribute concert in the coming weeks.

"This guy was one of those people who was just gifted," Kirwan said. "His music was wonderful. . . . It was just beautiful music."