An Indonesian family brought its 8-year-old daughter to a suicide bomb attack it launched Monday on the police headquarters in the country's second-largest city, authorities said, a day after members of another family conducted coordinated suicide bombings on three city churches that killed 12 people.
National police chief Tito Karnavian said the girl, who was with two of the attackers on a motorcycle, survived being thrown by the blast at Surabaya's police headquarters. The attack killed the four perpetrators. Six civilians and four officers were wounded.
The attack came just hours after police said the family that carried out the church bombings included girls ages 9 and 12.
The flurry of bombings raised concerns that previously beaten-down militant networks in the world's most populous Muslim-majority nation have been reinvigorated by the return of some of the estimated 1,100 Indonesians who went to fight with the Islamic State group in Syria. Experts have warned for several years that when those fighters return, they could pose a significant threat.
Islamic State claimed responsibility for the church bombings in a statement carried by its Aamaq news agency. Karnavian, however, said earlier police comments that the family had spent time in Syria were incorrect.
He said the church bombers and the police headquarters attackers were friends, as were members of another family whose homemade bombs exploded in their apartment Sunday night.
The use of children in the attacks has been particularly horrifying to people.
"This is terrifying," said Taufik Andrie, executive director of an institute that runs programs to help paroled militants reject extremism and rejoin society. "This is showing how extremist ideology can entrap children. Children have no choice. They can't comprehend the decisions involved."
All told, 25 people have died since Sunday including a total of 13 militants and their children.
Indonesian President Joko "Jokowi" Widodo condemned the attacks as "barbaric" and vowed that authorities would root out and destroy Islamic militant networks. The top security minister, Wiranto, who uses one name, said the government will attempt to hasten passage of an updated anti-terrorism law that has languished in parliament.
A security camera video of the attack on Surabaya's police headquarters showed at least one explosion after the four attackers rode two motorcycles up to a security checkpoint. The motorcycles, which moved closely together, pulled up alongside a car and four officers manning opposite sides of the checkpoint.