Forty-one people, including two police officers, were hospitalized with injuries, police spokesman Frans Barung Mangera said previously.
Officials say they foiled several planned attacks on Sunday, killing four suspected members of JAD and arresting two others.
IS claimed responsibility for the attacks in a message carried on its Amaq news agency.
Police said at least five suicide bombers were involved, including at least one on a motorcycle and a woman who had two children with her, according to The Associated Press. Based on their remains, Karnavian said the mother and daughters were all wearing explosives around their waists.
Police say the father crashed a auto loaded with explosives into one church, while his 2 sons aged 18 and 16 ignited bombs at an entrance to another church.
Forensic evidence indicates the bombs were attached to the attackers' bodies, Karnavian said.
Police investigate if grandfather is responsible for mass shooting
According to police , two adults were found outside of the property and the other five bodies were discovered inside the home. Pamela Townsend, president of the Shire of Augusta-Margaret River, said the deaths have impacted everyone in the community.
Police have closed all three areas as they examine.
The terror attacks by a family including young children sent shockwaves through Indonesia.
The investigators additionally discovered "black powder" on the properties, and officers seized books and paperwork from the home, Setiawan stated. "We are concerned that this has happened many times and has often occurred around Sunday services", said association spokesman, Jeirry Sumampow.
Pope Francis said, "Together let us call upon the God of peace, that He might bring these violent actions to an end; and that in the hearts of all, space might be found for feelings, not of hatred and violence, but of reconciliation and fraternity".
"No words can describe how deep our condolences are for the fallen victims".
"MFA and the Singapore Embassy in Jakarta have reached out to Singaporeans who are e-registered in Surabaya to ascertain their safety", the statement said, adding that there have been no reports so far of Singaporeans directly affected or injured by the bomb blasts.
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Rouhani did not mention Israel's strikes in Syria early on Thursday, or those against the Israeli-occupied Golan Heights, also on Thursday.
"These assaults on peaceable worshipers are an affront to the tolerance and variety embraced by Indonesians".
Indonesia, world's largest Muslim-majority country, has experienced a recent resurgence of local insurgent groups. More than 82% of its roughly 261 million people observe Islam. About 87 percent of the population is Muslim, while Christians make up about 10 percent, according to a 2010 estimate from the Central Intelligence Agency.
Indonesia has long struggled with domestic terrorist groups, particularly the al-Qaeda affiliated group Jemaah Islamiyah, which claimed responsibility for 11 attacks between 2000 and 2010, including the deadly 2002 Bali bombings that left more than 200 people dead and hundreds injured, many of them tourists. The Indonesian government reported past year that up to 500 of its citizens had journeyed to Syria in order to fight for ISIS.
Six suicide bombers targeted three Christian churches during services in Surabaya, the country's second-largest city. Authorities suspect ISIS involvement.
The bombings mark the deadliest terrorist incident in years.
Police shot and wounded an IS-inspired radical who attacked a church congregation outside Indonesia's cultural capital Yogyakarta with a sword during a Sunday mass in February.
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Giuliani with respect to what was intended by his remarks", a spokeswoman for the law firm said in a statement. Greenberg's executive chairman, Richard Rosenbaum , said Giuliani permanently left the firm on Wednesday.