COLOMBO (AFP) -- A series of eight devastating bomb blasts ripped through high-end hotels and churches holding Easter services in Sri Lanka on Sunday, killing at least 207 people, including dozens of foreigners.
The attacks were the worst act of violence to hit the country in the decade since the end of a bloody civil war that killed up to 100,000 people.
For many in Sri Lanka, the apparently coordinated attacks brought back painful memories of life during the long-running conflict, when bomb blasts were a frequent occurrence.
There was no immediate claim of responsibility but the government said eight people had been arrested and investigators would look into whether the attackers had "overseas links."
The government also imposed a nationwide curfew and curbed social media access to restrict "wrong information" spreading in the country of 21 million people.
The powerful blasts -– six in quick succession and then two more hours later -- injured hundreds.
At least two of them involved suicide bombers, including one who lined up at a hotel breakfast buffet before unleashing carnage.
By Sunday evening, the toll stood at 207 dead and 450 people injured.
Police said 35 foreigners were among the dead, including British, Dutch, Portuguese, Chinese and American citizens.
U.S. Secretary of State Mike Pompeo confirmed that "several US citizens" were killed.
Among the churches targeted was the historic St Anthony's Shrine, a Catholic church in Colombo, where the blast blew out much of the roof.
Bodies lay on the ground of the church, covered in patterned scarves and white sheets, some of them stained with blood.
Shattered roof tiles and shards of glass littered the floor, along with chunks of plaster blasted from the walls by the explosion.
Documents seen by AFP show that Sri Lanka's police chief Pujuth Jayasundara issued an intelligence alert to top officers 10 days ago, warning that suicide bombers planned to hit "prominent churches".
"A foreign intelligence agency has reported that the NTJ (National Thowheeth Jama'ath) is planning to carry out suicide attacks targeting prominent churches as well as the Indian high commission in Colombo," the alert said.
The NTJ is a radical Takfiri group in Sri Lanka that was linked last year to the vandalization of Buddhist statues.
Prime Minister Ranil Wickremesinghe, speaking late Sunday, acknowledged "information was there" about possible attacks and that an investigation would look into "why adequate precautions were not taken".
Rucki Fernando, a Christian Sri Lankan, told AFP: "We haven't experienced anything like this in the last 10 years."
"There is a lot of fear, not just in the Christian community, but among everyone."
Sri Lanka's Minister of Economic Reforms, Harsha de Silva, described "horrible scenes" at St Anthony's church. "I saw many body parts strewn all over," he tweeted, adding that there were "many casualties including foreigners".
Witness N. A. Sumanapala was near the church when the blast happened. "I ran inside to help. The priest came out and he was covered in blood," he told AFP.
"It was a river of blood."
A second blast hit St. Sebastian's Church in Negombo, north of the capital during Easter mass.
Gabriel, who declined to give his family name, told AFP his brother was injured in the explosion.
"We are all in shock. We don't want the country to go back to that dark past where we had to live in fear of suicide blasts all the time."
Soon after the first two church blasts, police confirmed that the Zion church in the east-coast town of Batticaloa had been hit, along with three high-end hotels in the capital -- the Cinnamon Grand, the Shangri-La and the Kingsbury.
A manager at the Cinnamon Grand, near the prime minister's official residence in Colombo, said a suicide bomber blew himself up at the hotel's restaurant.
"He came up to the top of the queue and set off the blast," he told AFP.
Later in the afternoon, two people died in a strike at a hotel in the south of Colombo, and a suicide bomber killed three police officers as they raided a house in a northern suburb of the city.
Wickremesinghe urged people to "hold our unity as Sri Lankans" and pledged to "wipe out this menace once and for all."
The Archbishop of Colombo, Malcolm Ranjith, described the attackers as "animals" and called on authorities to "punish them mercilessly".
Embassies in Colombo warned their citizens to stay inside, and Sri Lankan Airlines told passengers to arrive at the airport four hours ahead of flights because of ramped-up security.
Only around six percent of mainly Buddhist Sri Lanka is Catholic, and the country is a patchwork of different religious and ethnic groups, dominated by Buddhist Sinhalese.
Recent years have seen growing sectarian tensions, including accusations of hate crimes by extremist Buddhist monks against minority Muslims.
There have been no attacks in Sri Lanka linked to foreign groups, but in January, Sri Lankan police seized a haul of explosives and detonators following the arrest of four men from a newly formed Takfiri group.