A Butler man is facing assault and endangerment charges after police said he threw a liquor bottle that struck a woman in the arm, causing a large cut and leaving her semiconscious.

Butler police on Friday filed felony charges of aggravated assault and endangering the welfare of children and a misdemeanor count of reckless endangerment against Justin S. Thompson, 28, following an April 1 incident at a West Penn Street apartment.

Officers responded to an emergency medical call for a patient who was struck by a bottle and had a possible head injury, They said they found a woman collapsed on the front porch. A Butler Ambulance Service crew arrived and found her to be semiconscious with heavy bleeding from a large cut on the inner part of her upper right arm.

She was taken to Allegheny General Hospital by ambulance because poor weather prohibited a medical helicopter from flying, police said in an affidavit.

Two other women told police they saw the woman arguing with an unknown man and being struck with a glass liquor bottle. However, the witnesses gave different descriptions of the man, according to an affidavit in the case.

Eventually, one of the witnesses identified Thompson as the man who argued with and threw the bottle at the woman. She said the argument was over sexual advances Thompson was making. He threw the bottle that struck the woman in the arm as she tried to protect herself, according to the affidavit.

The witness told police Thompson fled and the woman chased him, but collapsed on the porch and was in and out of consciousness, according to the affidavit.

The woman gave police a similar account of the incident, which occurred in the presence of two children, according to the affidavit.