About 300 people held a prayer vigil Sunday for Xavier Stern, the Upper Darby teen found Friday in a 1998 Lincoln Town Car in North Philadelphia, dead from a single gunshot wound to the head.

The vigil was held on a football field that had served as a sanctuary for Stern, a sophomore at Upper Darby High School, whom many described as "loving and compassionate," but who had run into legal issues.

The discovery of his death came nearly three weeks after he left his family's home in Upper Darby, and just one day after his father reported him missing.

Richard Stern, 35, stood near the front of the vigil next to the stage on Sunday night and lashed out at the media for what he said has been an unfair characterization of his son.

"I'm extremely mad," Stern said. "Everything is being taken out of context about my son. He was not missing. He was on the run. But everyone knew where he was at. That's why I didn't report him missing until [Thursday]. By then, no one had heard from him or seen him."

On Sunday, police were still working to piece together the final weeks of Xavier Stern's life before his death in a debris-filled car in North Philadelphia.

Philadelphia police are investigating his death as a homicide, but as of late Sunday, investigators had no suspects or motive.

Upper Darby Police Superintendent Michael Chitwood said investigators also would examine why Stern's father, who had not seen him since Nov. 22, did not report him missing until Thursday.

"And then the next night [after he was reporting missing], he's found dead," Chitwood said. "What happened in between Nov. 22 and then, I have no idea."

Stern was arrested and charged with assault in March, accused of hitting another teen in the head with a BB gun at the Barclay Square Shopping Center in Upper Darby, Chitwood said. Stern was placed on house arrest and wore an electronic monitoring anklet; Chitwood said he was permitted to leave the house for school.

But Stern cut off his anklet after an argument with his family Nov. 22, Chitwood said, and left home. A warrant was issued for his arrest after he cut off the monitoring device.

In social-media posts, friends indicated that they had seen Stern since he left home, but his father told police he had not heard from his son in weeks.

Richard Stern blasted Chitwood and the police handling of his son's death.

"The police aren't telling me anything," he said at the vigil. "There was a surveillance camera near where this [murder] happened. How long does it take to pull stuff from a video camera?"

Stern, 15, played with the Overbrook Monarchs youth football league and used to live in the North Philadelphia neighborhood where his body was found before his family moved to North State Road in Upper Darby.

On Sunday, Stern's football coaches and teammates got on the raised stage and eulogized the teen, weeping openly over his death.

Many described the former linebacker and defensive lineman as scrappy and hardworking on the field.

"He never missed a practice," said Sonantonious "Sonny" Moore, president of the Overbrook Monarchs, who coached Stern for two years.

"Despite what you've read about Xavier, he was compassionate, loving, and funny. He was just trying to find his way," Moore said. "Do not pass judgment on this young man's life. Show his family respect during this painful time."

Onstage, Moore gave Stern's mother, Kia Downs, her son's No. 80 Monarchs purple jersey and a recent championship trophy. Downs had tears streaming down her face.

Stern's football teammates said he had a protective side.

"He was like a big brother I never had," said Brylan Brown, 14, of Upper Darby. "Just five days ago, while I was walking to practice, he told me, 'Be safe.' "

Visibly shaken was Nya Jones, 15, of Upper Darby, who was Stern's girlfriend of three years and three months.

"His grandmother called me about his death," Jones said. "I just cried and broke down on the phone."

She said she urged Stern to surrender to police just days before. "I said to him to do the right thing and turn himself in, and he'll do better."

Police said members of Stern's family were already at the scene on North Park Street when police arrived Friday. Police did not explain how the family found him in the car. Stern was found wearing a hood, with a single gunshot wound to the head. He was pronounced dead at the scene.

An owner of a club across from the football field shook his head in disbelief when told why the vigil was taking place.

"It's a shame," said the owner, who asked not to give his name out of fear of the shooter. "These kids often do things outside of the playground that get them into trouble, or into something they shouldn't be into.

"He was only 15."