Police in Greece's capital were searching for a gunman who opened fire at a social security office and a courthouse on Tuesday, wounding several people.

Greece's public broadcaster ERT reported that the alleged gunman was an 89-year-old man and a police operation was underway to locate the armed man.

What we know so far 

Police said the suspect opened fire with a shotgun at a branch of Greece's EFKA social security agency, wounding an employee in the leg.

The gunman then traveled by taxi to a court building, where he fired several shots inside, lightly wounding four female court clerks, police and court officials said.

The motive for the shooting was unclear. ERT said the gunman had fled the scene but reportedly left letters with documents after the shooting at the courthouse.

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

This developing story will be updated as more information becomes available.

Edited by: Alex Berry