Investigators released surveillance images Wednesday of the suspect in last week’s shooting of a Philadelphia Parking Authority officer in Frankford.

The gunman shot the officer, a 37-year-old man who was on duty, just before 4 p.m. Friday on the 4500 block of Frankford Avenue, according to authorities. Police said the victim was seriously injured, with wounds to his head and right shoulder.

Detectives described the suspect as between 5 feet 9 inches and 6 feet tall with a thin build. He was wearing a navy blue hooded sweatshirt, green cargo pants, black mask, gloves and black boots at the time of the shooting.

Anyone with information is asked to contact the PPD’s Shooting Investigation Group at 215-686-8270; call or text 215-686-8477; or leave a tip at www.phillypolice.com/forms/submit-a-tip.

The city and PPA are offering a $20,000 reward for information that leads to an arrest and conviction in the shooting.