PITTSBURGH -- Pittsburgh police have joined the search for a 17-year-old Schenley High School senior who has been missing since Friday, and they are asking for the public’s help.

Joseph Harris, of Sheraden, is described as a black male, 5 feet 2 inches tall with black hair and brown eyes.

He was last seen at about 4 p.m. Friday in downtown Pittsburgh on the 16B bus on Liberty Avenue on his way to work in Robinson.

Harris' sister, Ashley Harris, spent most of Tuesday handing out flyers, hoping someone will recognize her brother.

"I don't know what else to do," she said. "I try to keep moving. Hopefully somebody will recognize him and call us. That's what I'm hoping."

Joseph Harris' parents said he is a good kid who's never had trouble and asked that if anyone has seen their son to please call police.

"We just want our son to come home. He's not a problem kid. He goes to school. He goes to work. We have concerns about what's going on," said Joseph Harris Sr.

"He’s a really good kid, well loved. And please baby, if you see us, please come home. This is your year to graduate. Please come home, I beg you," said Carla Harris.

Friends said that Joseph Harris last told them that he was going to the North Side to meet up with someone named "Gene."