Updated at 12:53 a.m. ET Monday
Nearly 300 people were killed and hundreds more wounded after explosions tore through Sri Lanka in a series of coordinated blasts that struck three churches and three hotels. It marked the country's worst violence since the end of its civil war in 2009.
Police spokesman Ruwan Gunasekara said Monday the death toll had risen to 290 dead with more than 500 wounded, according to The Associated Press.
A top police official reportedly had alerted security officials 10 days earlier about a threat to churches from a radical Islamist group, National Thowheeth Jama'ath. It was unclear what precautions, if any, had been taken, or whether that group had played any role in the assaults, according to The New York Times.
Sri Lanka's prime minister, Ranil Wickremesinghe, pointedly said he and other ministers had not been warned, in what appeared to be a sign of the recent frictions within the government hierarchy, the paper adds.
The blasts started as people gathered for Mass on Easter Sunday. In Colombo, the country's capital, bombings were reported at St. Anthony's Shrine and three high-end hotels: the Shangri-La, the Cinnamon Grand and the Kingsbury.
Explosions were also reported at St. Sebastian's Church in Negombo, north of the capital, and at Zion Church in Batticaloa, in the country's Eastern Province. A police spokesman, Ruwan Gunasekara, said at least 207 people were killed and 450 wounded in the attacks.
The blasts gave way to sounds of screams and cries as billowing smoke could be seen from the streets. Inside the churches, devastated worshippers stood near pews covered in rubble and blood. A similar scene of destruction was reported at the luxury hotels that were attacked.
No one has claimed responsibility for the attacks, but police say 13 suspects linked to the explosions have been arrested, The Associated Press reported. Sri Lanka's defense minister, Ruwan Wijewardene, described the violence as a terrorist attack carried out by religious extremists and said he believed they were part of one group.
Prime Minister Ranil Wickremesinghe, who condemned the "cowardly" attacks, told reporters that information about the bombings appeared to have been received in advance. "We must look into why adequate precautions were not taken. Neither I nor the ministers were kept informed," he said at a news conference.
St. Sebastian's Church posted photos of the aftermath on Facebook, pleading for relatives to "come and help if your family members are there."
Harsha de Silva, Sri Lanka's minister of economic reforms and public distribution, said he visited the shattered churches, and he described the horrific scenes. "I saw many body parts strewn all over. Emergency crews are at all locations in full force," he said on Twitter.
"It was a river of blood," a shopkeeper named N.A. Sumanapala near St. Anthony's Shrine told The New York Times. "Ash was falling like snow," he said. "I saw limbs and heads. There were children too."
After the explosions, the government announced a curfew, which has since been lifted.
Easter services scheduled for Sunday evening were canceled, Sri Lanka's state news agency reported, and the government moved to block social media sites, including Facebook and Instagram, to stop the spread of false information. The Sri Lanka Red Cross said misinformation had already begun to spread online about its building being attacked, and it sought to dispel the rumor.
"We will go after them," Defense Minister Wijewardene vowed. "Whatever religious extremism that they are following, we will take the necessary actions against them and will stop these groups from operating in this country in the near future."
Wijewardene also said that three police officers had lost their lives during a search for suspects after explosives detonated.
The foreign minister said at least 27 foreigners were killed. A Portuguese national, a Dutch national, two Turkish engineers, at least three British citizens and several Chinese citizens were reported among the dead.
"Several American citizens" were also among the victims, a spokesperson for the U.S. State Department told NPR.
U.S. officials are advising Americans in Sri Lanka "to remain sheltered in place and to follow news reports," the spokesperson said. The U.S. Embassy in Colombo gave Americans who might need help a phone number to call to reach embassy staff.
World leaders offered their condolences as details of the assault mounted.
During his Easter Sunday Mass at the Vatican, Pope Francis took time to offer condolences to victims of what he called "such a cruel act of violence."
President Trump tweeted a message of support for Sri Lanka on Sunday morning, saying, "The United States offers heartfelt condolences to the great people of Sri Lanka. We stand ready to help!"
Muslims in Sri Lanka have also condemned the violence. All Ceylon Jamiyyathul Ulama, a Sri Lankan-based group of Islamic clerics, denounced the attacks on Christian places of worship.
Sri Lanka, a small island nation in the Indian Ocean, is primarily Buddhist. Less than 10% of the country identifies as Catholic, according to Sri Lanka's Department of Census and Statistics.
Religious and ethnic tensions have plagued the tropical country for years. A civil war started in 1983 and ended in 2009 after security forces defeated the Tamil Tigers, rebels who were fighting for an independent homeland.
Sunday's violence came just ahead of the 10-year anniversary of the end of Sri Lanka's civil war.
"We don't really have all the answers we want about who was behind the attacks," the U.S. ambassador to Sri Lanka, Alaina Teplitz, told NPR. "I don't believe they were linked to that conflict period, but for a country trying to recover, trying to achieve reconciliation among the ethnic and religious groups here, this is not going to support that effort."
This is a developing story. Details may change as more information becomes available.