The death toll from Easter Sunday's suicide bomb attacks on churches and hotels in Sri Lanka soared Monday to 290, including 39 foreigners, with authorities blaming foreign-backed "local terrorists" for the carnage and invoking emergency powers.
"The intelligence agencies have reported that there were international organizations behind these acts of local terrorists," President Maithripala Sirisena's media office said in a statement, after he chaired an emergency meeting of National Security Council.
The statement said Sri Lanka welcomes international assistance to pursue those responsible for the attacks, for which authorities have so far arrested a total of 24 people, 11 of them on Monday.
(Sri Lankan officials inspect St. Sebastian's Church after the explosion)
"The government has decided to Gazette the anti-terrorism legal clauses to be effective with effect from midnight today," it said, referring to clauses that give police and the military extensive powers to detain and interrogate suspects without court orders.
Health minister Rajitha Senaratne, who is also Cabinet spokesman, told reporters that police units earlier this month received information that the leadership of National Thowfeek Jamaath, a little known local Islamist militant group, was planning a series of attacks in the country.
But he said Prime Minister Ranil Wickremesinghe was not informed of those warnings as he has been excluded from National Security Council meetings chaired by the president, and as a result, "adequate precautions" were not taken to prevent the attacks.
Political instability has rocked the nation recently after Sirisena abruptly sacked Wickremesinghe last October and named former President Mahinda Rajapaksa as his successor, only to see Wickremesinghe return as premier after weeks of chaos.
"We don't believe that these attacks have been carried out by group of people who were confined to this country only," Senaratne said. "There is an international network, without which these types of attacks could not have succeeded."
The eight explosions, which occurred mostly in and around Colombo, mark the worst violence that the South Asian island nation has seen since the end of its civil war a decade ago.
A ninth explosion reportedly went off on Monday in a van parked near St. Anthony's Shrine, one of the three churches targeted the previous day, when bomb squad officials tried to defuse it.
It was also reported Monday that Sri Lankan police found 87 bomb detonators at Colombo's main bus station.
Tourism Minister John Amaratunga was quoted by the Associated Press as saying 39 foreign tourists were killed in the blasts, while another 28 were among the more than 500 injured.
(Damage at the Kingsbury)
The fatalities included British, Indian, Danish, Australian, Chinese, American and Dutch nationals, with the Japanese Foreign Ministry confirming one Japanese dead and four injured.
Also at Monday's National Security Council meeting, it was decided to implement anti-terrorism measures, grant additional powers to the police, impose an overnight police curfew, boost security at Catholic churches and declare Tuesday a national day of mourning.
Among the three hotels in central Colombo targeted in the attacks was the Cinnamon Grand, which is popular among politicians and foreign tourists.
A staff member of the hotel told Kyodo News that a suicide bomber detonated an explosive where a breakfast buffet was being served. "Most of the people sitting inside the restaurant died," the employee said.
The other two hotels were the Shangri-La and the Kingsbury, also popular among foreign tourists.
The three churches attacked were St. Anthony's Shrine in Colombo, St. Sebastian's in Negombo, north of Colombo, and Zion Church in Batticaloa on the country's east coast. Many worshippers had gathered for Easter Sunday celebrations.
Separately there was a blast at a hotel in the suburbs of Colombo. Three police officers were also killed in a residential area of the capital when a suspect being questioned by the police detonated a suicide bomb.
Sri Lanka had enjoyed a decade of peace since a bloody 26-year-long civil war between the government and Sri Lankan Tamil militants ended in 2009.
Buddhism is the dominant religion in Sri Lanka, being practiced by around 70 percent of the population. Less than 10 percent of its people are Christian, around 10 percent Muslim and another 10 percent Hindu.