Locked in a struggle with a drug-seeking gunman, Dr. Parvis Jian pulled a black ski mask from his assailant's face and confirmed what he already knew: The man pistol-whipping him in his office was a patient he'd been treating for months.

Wednesday was to be the man's final appointment, he told police.

In a criminal complaint against William Scannell, the man charged with robbing and assaulting the doctor, police said he fled Dr. Jian's office in Bellevue with $330 and 67 tablets of suboxone, a prescription given to treat addiction to opiates, such as heroin.

Police said Mr. Scannell fired four shots and struck the doctor and his wife, Forouhar Jian, with a silver handgun before fleeing the professional building. The incident spawned a manhunt that ended early Friday, when Allegheny County sheriff's deputies arrested him in Oakland.

Charges against Mr. Scannell, 35, include aggravated assault, reckless endangerment, robbery and theft. He was being held in the Allegheny County Jail on $200,000 bond, and a judge ordered him to be evaluated in the jail's behavioral clinic.

Dr. Jian and his wife, who is also his office manager, both suffered lacerations to the head and face, the complaint said. Mrs. Jian also suffered a burn to the left side of her face from the gun's muzzle blast.

She told police that Mr. Scannell called the office on Lincoln Avenue about 5 p.m. Wednesday to tell her he would be late for his 5:30 p.m. appointment. Dr. Jian planned to drop Mr. Scannell as his patient, according to the complaint.

About 5:30, after other employees had left, a gunman entered the office wearing gray coveralls, a black ski mask and sunglasses and ordered Mrs. Jian to "take it off!" According to the complaint, she later realized he was referring to a fanny pack worn around her waist, where she keeps suboxone.

Mrs. Jian then struggled with Mr. Scannell, who "struck her repeatedly about the face and head," the complaint said. When the doctor tried to intervene, he was also beaten, and Mr. Scannell pointed the gun at the pair several times. The doctor told police his attacker pointed it directly at him and fired one shot, then fired three more toward both of them.

After the fourth shot was fired, Dr. Jian said he was able to pull off the man's ski mask. He told police "he already knew that Scannell was the man who was attempting to rob them," but could clearly see his face after the mask was removed, according to the complaint.

Mr. Scannell is prohibited from possessing a firearm due to past convictions for robbery and burglary, police said. A preliminary hearing is scheduled for this week.

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