PHILADELPHIA (CBS) – Philadelphia police have not yet filed charges in the murder of Officer Moses Walker Jr., but more details regarding the criminal history of the 23-year-old person of interest have emerged.

Rafael Jones, who police believe is the triggerman in Officer Walker’s death, was picked up by U.S. Marshals at the Bartram Village Apartments in Southwest Philadelphia Wednesday afternoon.

According court documents obtained by Eyewitness News, Jones has a criminal history of drug and weapons charges.

“He’s a thug, he’s a career criminal. I don’t know what else I can say about him,” said Police Commissioner Charles Ramsey.

Court records indicate Jones was arrested and jailed in February 2012 for violating his probation from a 2008 weapons charge in which he was sentenced to two to four years in prison.

On July 25th, Jones was ordered to wear an electronic monitoring device when he was released from jail on August 8th; he was scheduled to have that device attached Wednesday, but failed to appear for his appointment with his probation officer.

With Jones in custody on an apparent parole violation, police say they now know the second suspect caught on surveillance video the night Officer Walker was gunned down in North Philadelphia. They are considering releasing his photo to the public if he does not turn himself in.

“We are very confident. We have some of the best detectives around upstairs. We feel like we’ll have him very soon,“ said Captain James Clark.