Indonesia: Explosion at police headquarters in Surabaya kills seven

An explosion at the police headquarters in Indonesia's second biggest city Surabaya killed at least seven people on Monday. The deadly explosion comes just a day after a family of six including two young daughters staged suicide bombings at three churches in Surabaya during Sunday services.

Citing CCTV footage from the scene, East Java Police spokesman Frans Barung Mangera said a man and a woman on the bike stopped at the security checkpoint. "That's where the explosion happened," he added.

"Two people were riding (on the motorcycle) and a woman was sitting at the back."

Frans Burung Mangera said the explosion killed three people: a father, mother and their child. Two other children, a son and daughter from the same family, were rushed to Siti Khodijah hospital for treatment.

Police are investigating possible links between the Sidoarjo and Surabaya blasts but are yet to provide further details.At least 14 have died as a result of that attack, which was claimed by the Islamic State group, and the toll could climb with more than 40 injured in hospital.

The church bombers a mother and father, two daughters aged nine and 12, and two sons aged 16 and 18 -- were linked to local extremist network Jamaah Ansharut Daulah (JAD) which supports IS, police have said.

A further three people in one family were killed and two wounded when another bomb exploded at an apartment complex about 30 kilometres from Surabaya, just hours later, police said.

The mother and one child died from the explosion while police said they shot dead the father who was carrying a bomb detonator.

Two other children were injured in the blast and were taken to hospital. There was no immediate claim of responsibility for the apartment bomb.