PENN HILLS, Pa. -- A man accused of beating and stabbing two Penn Hills teenagers to death on Tuesday underwent a behavioral evaluation on Friday.

Keith Scott, 40, was arrested Wednesday and charged with killing Leisha Drake, 18, and her 14-year-old brother, Naim Drake, at an apartment in the Hulton Estates complex, Allegheny County police and the medical examiner's office said.

Scott was arraigned via videotape since he is on suicide watch at Allegheny County Jail. No bond was set.

He is charged with two counts of homicide and aggravated assault, among other charges.

Police said his girlfriend, the mother of the teens, was found in the basement, stabbed in the face and chest. She was taken to a Pittsburgh-area hospital, but her condition and identity have not been released.

Her son, Naim, was found dead in the living room. Her daughter, Leisha, was found in an upstairs bedroom. Police said the two were beaten with a dumbbell and stabbed. Both died of blunt-force trauma to the head.

Police said Scott fled the scene in his girlfriend’s car and was later arrested.

Authorities have not released any information regarding a motive for the crime.

Scott is scheduled to undergo a behavioral evaluation Friday.

His defense attorney, Jim Ecker, said Scott is a decorated combat veteran with no history of violence.

"I'm sure he has had problems in his life," said Ecker. "I don't know what his record is. Everybody has problems in their life. I don't know anybody that hasn't. However, as far as I know, he's never done anything like this in his life, where he's done anything violent to somebody. The whole family's upset, and I'm sure that the family of the victims are very, very upset, too. It's just a very difficult day for everybody."

Scott's preliminary hearing is scheduled for Oct. 24.