The group began the assault by ramming a car into the police headquarters in the town of Pekanbaru in Riau province.

A police officer was killed and one of the assailants arrested. The Islamic State (IS) group has claimed the attack via its news outlet.

It comes after a series of suicide attacks carried out by families that have shocked the country.

Police blame a local IS-inspired group, Jemaah Ansharut Daulah (JAD), for the attacks in the city of Surabaya.

Indonesia is the world's most populous Muslim-majority country.

Following the 2002 Bali bombings, it had been widely praised for its sustained anti-terrorism crackdown.

Parents who bring their children to die
Why is Indonesia a target for IS militants?
It managed a combination of arrests and killings, alongside a de-radicalisation program that focused on changing minds and providing alternative incomes for released terrorists.

But, the country now faces a new threat, in part from from IS fighters who have come home after combat in Syria.