A police spokesman says there has been an explosion at the police headquarters in the Indonesian city of Surabaya after an apparent vehicle attack.

In a news conference on TVOne, Frans Barung Mangera said officers had been injured in the Monday morning attack. He said the vehicle used was a motorcycle.

The attack follows suicide bombings at three churches in the city on Sunday that killed at least eight members of the public as well as six people from one family who carried out the bombings.