Greek authorities say a small incendiary bomb has exploded outside the deputy minister for police's private office and caused minor damage but no injuries.
Two more similar devices failed to explode outside the private offices of Justice Minister Haris Kastanidis and governing Socialist lawmaker Chrysi Arapoglou in central Thessaloniki.
All three devices were made of camping gas canisters tied together.
A police statement says the entrance to Deputy Citizen's Protection Minister Spiros Vougias' office was slightly damaged by the blast. Two women working in his basement office jumped out of a window and suffered no injury.
There has been no claim of responsibility for Friday's attacks. Greek anarchist groups frequently target symbols of wealth and state authority, using gas canister bombs.
