Here's what we know so far about the Sri Lanka attacks

A coordinated series of bombings ripped through churches and hotels on Easter Sunday, killing at least 290 people and injuring hundreds more.

Sri Lanka’s minority Christian community — which accounts for less than 10% of the country’s total population of 21.4 million — appeared to be the main target of the attacks.

Here's what we know so far:

What happened:

The victims:

The aftermath:

US Secretary of State Mike Pompeo said the fight against terrorism in Sri Lanka, “is America’s fight too.”

“Radical Islamic terrorism remains a threat. The president has been very clear about that, I think I have been very clear about that. We are continuing to do real work against these evil human beings that went into places of worship on Easter Sunday,” Pompeo told reporters at the State Department on Monday.

He called for “any evil doers be brought to justice expeditiously.”

Dieter Kowalski from Colorado has been identified as one of the Americans killed in the attacks in Colombo on Sunday, according to Pearson, the education publishing company that Kowalski worked for.

“Dieter had just arrived at his hotel, where many of our colleagues have stayed over the years, when he was killed in an explosion,” Pearson CEO John Fallon said in a statement.

Dieter’s brother Derrick Kowalski confirmed his brother’s death on Facebook, writing, “as we know that Dieter saw his friends as family, we would like to share our grief over this tragic incident.”

The initial intelligence indications are that the group responsible for the attacks in Sri Lanka was inspired by ISIS, a US official has told CNN.

At this point, no group has claimed responsibility for the attacks.

The official said at least four US citizens have been killed.

It was unclear if the US death toll included the two dual US-UK nationals who were among the eight UK nationals confirmed dead.

A day after a series of coordinated blasts rocked Sri Lanka, officials still appear to be trying to get a handle on the situation on the ground.

What the investigation has turned up so far on Monday:

Hours after the initial blasts, a six-foot-long pipe bomb was found on Sunday night near the road leading to Sri Lanka’s Bandaranaike International Airport.

With the situation in flux, residents are preparing to hunker down for the night as a curfew comes into effect across the island from 8 p.m. (10 a.m. ET) until 4 a.m. (6 p.m. ET). It's the second night Sri Lankans have been asked to remain indoors after sunset.

At least 39 tourists were killed in the Sri Lanka bombings on Easter Sunday, the country’s tourism minister said on Monday.

John Amaratunga, the minister of tourism, wildlife and Christian religious affairs, also confirmed 28 tourists are currently receiving hospital treatment following the attacks.

“I wish to assure the tourism industry that the government has taken every possible measure to ensure the safety of the public and all tourists who are in the country. The three armed forces along with the police have put in place a comprehensive security plan covering hotels, resorts and places of tourist interest,” Amaratunga said in a statement.

A bishop at the St. Sebastian church -- one of the sites targeted in Sri Lanka on Easter Sunday -- told CNN he would have never dreamt that his community's house of worship might be targeted in an attack.

"We never expected such a thing to happen, especially in a place of religious worship,” Bishop JD Anthony said Monday. “This church is in a very rural area so we never expected this to happen here.” 

He suggested the attacker might have chosen the church because of the large number of people who attend the services here. On the morning the bomb went off, more than 1,000 worshipers had gathered for the Easter service.

“We have more than 100 people who were killed on the spot and so many others injured. We are still in an atmosphere of shock.” 

He said they don’t know what to do, “only to pray, that is our most important and powerful weapon.”

“I fear the motive of doing this” might be to increase community tensions, though he added “we never had” this type of attack previously. 

“I couldn’t sleep because of this. Innocent people who came to pray here ... they sacrificed their life for god.”

The Sri Lankan government has admitted it failed to act on multiple warnings before a coordinated series of attacks ripped through churches and hotels on Easter Sunday, and said it feared an international terror group might have been behind the atrocities.

A government spokesman, Rajitha Senaratne, said multiple warnings were received in the days before the attacks, which killed 290 people and injured at least 500 more. CNN understands that at least one warning referred to Nations Thawahid Jaman (NTJ), a little-known local Islamist group which has previously defaced Buddhist statues.

Senaratne, who is also health minister, said he did not believe a local group could have acted alone. “There must be a wider international network behind it,” he said.

There were also fears of more devices following the attack. A ninth improvised explosive device (IED) was defused near the capital’s Bandaranaike International Airport on Sunday evening. And on Monday, police found 87 detonators in a private terminal of the main bus station in the capital Colombo.

Sri Lankan police performed a controlled detonation Monday of a suspicious van near St. Anthony’s church, which was one of the churches targeted in Sunday’s coordinated attacks in Colombo.

CNN’s Ivan Watson is at the scene and described the explosion as “a very big blast” which “knocked down a security officer” and blew out the windows in the street.

Police have pushed onlookers back and established a cordon around the site.