A group of boys caused significant damage to an ACT government building in Curtin, police say.
Police said they were called to Carruthers Street about 9pm on October 24 regarding the incident.
By the time officers arrived, the alleged offenders had fled.
Police said they saw significant damage to the building, and believe a group of three or four boys was behind it.
The boys were described as Caucasian. One of them was reportedly seen one riding a blue mountain bike and wearing a helmet. A second rider was blonde and rode a black mountain bike with a large white brand on the frame while another was on foot carrying a blue-grey backpack, according to police.
"Police would like to speak to anyone who witnessed the incident or who may have information relating the identity of the boys," ACT Policing said.
They asked people with information to contact Crime Stoppers on 1800 333 000, or on the Crime Stoppers ACT website and to quote reference 7574405.