PHILADELPHIA -

Police Commissioner Charles Ramsey confirmed Tuesday night that a K-9 officer is being investigated on rape allegations.

Ramsey would not release any more information except to say the Philadelphia District Attorney's Office is also involved in the investigation.

The allegation is that the officer raped an unconscious woman in the back of his marked police car, FOX 29's Steve Keeley reported Wednesday morning.

"We're right on top and, again, we'll deal with it the swiftest way that we possibly can," Ramsey said at a news conference Tuesday night in Germantown just after his return from a conference in California.

This is, of course, the second incident of police brutality under investigation in the department, the other being the case of the lieutenant who was caught on camera hitting a woman at the Puerto Rican Day Parade over the weekend.

Ramsey says the video is "very troubling" in that case, adding, "from what I saw, it's difficult to justify the actions that took place."

And those aren't the only issues the commissioner is dealing with.

Another Philadelphia police officer was also arrested Monday on accusations of driving under the influence.

Investigators say Sgt. Chanta Herder was off-duty when she crashed into another car on the 7900 block of Verree Road in Northeast Philadelphia. She blew over the legal limit when given a breathalyzer test.

Herder is now on administrative duty.