Four motorcyclists exploded in the police station in Indonesia's second largest city, Surabaya, injuring at least 10 people, including police, authorities said a day after a deadly wave of suicide bombings in several churches.

Referring to a footage from video cameras in the area, initially, the police spokesman Franco Barung Mangera reported that a man and a woman on a motorcycle had stopped in front of the security service. "That's where the explosion has happened," he added.

Four policemen and six local citizens were injured.

A young girl surviving the attack is the third of the motorcyclists. On the same motorcycle was also an eight-year-old child who was taken to a hospital.

The attack came a day after six suicide bombers attacked three churches in the same city. They died as well as another 17 people.

About 45 people were injured. The terrorist organization Islamic State has taken responsibility for the attacks in the churches.