A gunman opened fire at a social security office and at a courthouse in central Athens on Tuesday, wounding several people, Greek authorities said.

A police operation was underway to locate the gunman, who Greek media reported was an 89-year-old man.

Police said a suspect armed with a shotgun initially opened fire at a social security office in the center of the Greek capital, wounding an employee.

Police officers who arrived at the scene treated the man, but the gunman fled the scene.

The same man was suspected of later opening fire on the ground floor of a court building in another part of central Athens, with several people wounded there, police said, adding that authorities had found the shotgun.

Footage from state broadcaster ERT showed ambulance crews transporting at least three people from the courthouse to waiting ambulances.

The motive for the shooting was unclear.

ERT said the gunman had reportedly thrown envelopes with documents onto the floor after the shooting at the courthouse, saying those were the reasons for his actions.

Alexandros Varveris, head of the National Social Security Fund known by its Greek acronym EFKA, said that the gunman had gone to the fourth floor of the social security fund’s offices in the Kerameikos area of central Athens and opened fire after calling out to an employee “to duck.”

His shot hit another employee, who was wounded in the leg, Varveris said, adding that the gunman had been wearing a trenchcoat under which he had hidden the shotgun.

“He went in, went up to the fourth floor, raised his shotgun, told an employee to duck and hit another one,” Varveris told ERT radio. He said that it didn’t appear that the gunman had specifically targeted the employee he hit.

The wounded employee was transported to a hospital, after police applied a tourniquet to his leg at the scene.

Gun violence is relatively rare in Greece, where firearm ownership is allowed but tightly regulated.