Indonesia bombings that killed 8 in churches continue for 2nd day ISIS claimed responsibility for attacks Sunday that targeted churches.

London -- A day after at least 8 people were killed in suicide bombings in churches in Indonesia, suspected militants attacked a police headquarters in the same city of Surabaya, the country's second largest.

Police believe six members of one family carried out Sunday’s deadly, back-to-back bombings that targeted three churches ahead of Sunday Mass.

Monday’s attack on the police station involved a group of suicide bombers on two motorcycles who were stopped at a checkpoint outside the station.

Details are not yet clear on the number of casualties.

“We are still investigating on whether the explosion came from a car or a motorcycle," a Surabaya police spokesman said. "We can confirm a police officer was a victim of the explosion, but we cannot confirm now if it’s just an injury or death.”

Four officers are injured, according to The New York Times. The Times reported that four attackers died in the incident, and a young girl who was also on a motorbike has been taken to hospital.

The suicide bombers are believed to be a family of suspects, similar to those suspected of the church attacks Sunday.

Indonesian President Joko Widodo condemned the church bombings as “barbaric” attacks that they went against the country’s multifaith values.

“This act of terrorism is really barbaric and beyond the limit of humanity. It has inflicted casualties among the people, police and innocent children, including the perpetrator herself and her 10-year-old children, who acted as suicide bombers,” he said.

Indonesia’s national police chief said that the family of suspects in the Sunday attacks had recently returned from Syria.

ISIS claimed responsibility on its online channels, saying the attacks were carried out by its followers.

Pope Francis during Sunday Mass in Vatican City offered prayers for the victims.

“I am particularly close to the beloved people of Indonesia,” he said. “Especially to the Christian communities in Surabaya, strongly hit by the attack against the churches. I pray for all the victims and their relatives. Let’s invoke together the God of peace, in order to stop these violent actions, may everyone’s hearts host sentiments of reconciliation and brotherhood, not sentiments of hate or violence.”

Indonesia is a majority-Muslim nation, with less than 9 percent of its population registered as Christian. However the country has a pluralist and multifaith constitution, with Islam, Catholicism, Protestantism, Buddhism and Hinduism recognized as the five official religions.

However, Christians face discrimination and difficulties in practicing their faith in certain parts of the country, and there has been an uptick in radicalism since the start of the Syrian civil war.

Indonesia's security services have succeeded in broadly clamping down on domestic terror cells since the Balinese bombings of 2002, which killed over 200 people.