By Brad Segall

BENSALEM, Pa. (CBS) — Authorities in Bucks County have now filed murder charges against a 27-year-old Bristol Township man saying he “tortured” his girlfriend’s 18-month old daughter who died of her injuries last week.

Adrian Allen was babysitting his girlfriend’s three children inside their Knights Road apartment in Bensalem last month when she returned home and found the toddler unresponsive in her crib.

Police now believe Allen made up a story that the girl knocked over some kitchen chairs and that’s how she got hurt.

“We’re still putting the pieces together,” says Bensalem Public Safety Director Fred Harran. “But it looked like he was just unable to deal with this child and reacted or beat her so bad that she died. He wasn’t able to control himself.”

District Attorney David Heckler says it appears from the autopsy that the girl had been abused for at least several weeks and maybe longer. The preliminary cause of death is head trauma.

Heckler says two other children are now with their grandmother.

Allen is being held in the Bucks County prison without bail.