As his relatives prepared for funeral services for 15-year-old Antonio Q. Clarke, they and police struggled with the question of who brutally killed the high school sophomore from Southwest Philadelphia.

Clarke, who attended Bartram High School, was found slain Nov. 26 in the 1200 block of Napa Street in the Grays Ferry section of South Philadelphia.

Police said that Clarke's throat was slashed and that he was stabbed many times in the back. He was found partly naked with plastic bags placed over his head, feet and torso, police said.

Marie Clarke, Antonio Clarke's mother, said he had never been involved in crime or violence and that he had a job at a nearby community center.

"He had friends all over the neighborhood," Clarke said yesterday afternoon as she stood next to a dining room table filled with condolence cards at her home in the 1200 block of Bonaffon Terrace in the Elmwood section of South Philadelphia.

She said her son had "no enemies. He traveled all over Philadelphia." She described him as a normal 10th grader who enjoyed school.

While police said there were no suspects or motive in the slaying, Clarke said she thinks her son was robbed.

She said his attackers removed his clothes "because he knew so many people," Marie Clarke said, adding that someone would have recognized his clothing. "They robbed and stripped him of everything, so I think it was someone he knew."

She said his cell phone and keys were missing. "That phone was like a diary for him," Clarke said.

Outside his home yesterday was a memorial of stuffed animals and lighted votive candles that friends assembled.

A viewing was scheduled for 10 a.m. today at the Frances Funeral Home at 6318 Elmwood Ave. with the funeral set for 11 a.m.

Contact staff writer Vernon Clark at 215-854-5717 or vclark@phillynews.com.