A Brunswick man accused of hitting his 91-year-old father repeatedly with an aluminum baseball bat pleaded not guilty Thursday to attempted murder and elevated aggravated assault.

Christopher Porter, 49, slight, balding and dressed in an orange jail uniform, shuffled and squinted as he was led into court at the Cumberland County Courthouse in Portland.

When police arrived Oct. 16 at the family’s home at 550 Merepoint Road in Brunswick, they found Porter’s father, James E. Porter, still conscious and seated on a living room chair with blood coming from a jagged 6-inch wound on his head and defensive wounds on his arms and hands, according to police reports in Christopher Porter’s court file.

Christopher Porter’s mother, Maureen D. Porter, directed the officers to a bedroom, where they found Christopher Porter with blood on his arms and the bat placed on a stand, the report says.

“During an in-custody interview, Christopher Porter informed Detective (William) Moir that he struck his father with a baseball bat approximately 3 times in his head and then approximately 5-10 times in his body,” Brunswick police Detective Greg Mears wrote in an affidavit used to obtain a search warrant of the Porters’ home.

As emergency workers transported James Porter to Maine Medical Center in Portland, his blood pressure declined and they began treatment. He was initially listed in critical condition at the hospital, according to a Brunswick Fire Department report included in the court file.

James Porter told emergency workers that his son struck him about 24 times with the baseball bat, the report says. His injuries included skull swelling, a damaged ear, deformed nose and possible arm fractures.

James Porter has since been released from the hospital, Assistant District Attorney Katherine Tierney said in the courtroom. She declined after the hearing to comment further on his condition.

Christopher Porter has been in custody since his arrest the day of the attack and is being held at the Cumberland County Jail on $100,000 cash bail.

Porter’s attorney, Robert Ruffner, reserved his client’s right to argue bail at a later date. Throughout the hearing, Ruffner positioned himself in an attempt to shield his client from a news photographer’s camera, and unsuccessfully asked court security officers if Porter could move to a corner of the courtroom where it would be difficult to photograph him.

Judge Lance Walker asked whether Ruffner intended to seek a psychological exam to determine his client’s mental competence. Ruffner said he was not yet requesting that but may do so in the future.

Porter, who speaks with a speech impediment, said little during the hearing, other than to acknowledge the charges against him and enter his pleas of not guilty. He has no prior criminal record, according to the State Bureau of Identification.

The charges of attempted murder and elevated aggravated assault are both Class A felonies, punishable by up to 30 years in prison.