Sri Lanka's Easter Sunday bombings were retaliation for a recent attack on mosques in New Zealand, the country's state minister of defence said.
Ruwan Wijewardene made the comment to politicians in parliament on Tuesday without providing evidence or explaining where the information came from about the attacks that killed 321 people.
"The preliminary investigations have revealed that what happened in Sri Lanka was in retaliation for the attack against Muslims in Christchurch, but we are continuing investigations," Wijewardene said.
Fifty people were killed in shooting attacks on two mosques in the New Zealand city of Christchurch on March 15.
The office of New Zealand's Prime Minister Jacinda Ardern said she is aware of comments linking the bombings to the mosque attacks in Christchurch, though it hasn't "seen any intelligence upon which such an assessment might be based".
A little-known Muslim organisation, National Thowheed Jamath (NTJ), has been linked to the worst attacks on the Indian Ocean nation since its civil war ended a decade ago.
Wijewardene said that along with NTJ, another local group, Jammiyathul Millathu Ibrahim (JMI) was also believed to be involved in the attacks.
Wijewardene also blamed "weakness" within Sri Lanka's security apparatus for failing to prevent the coordinated bombings.
"By now it has been established that the intelligence units were aware of this attack and a group of responsible people were informed about the impending attack," Wijewardene said.
"However, this information has been circulated among only a few officials."
Meanwhile, the Islamic State of Iraq and the Levant (ISIL, ISIS) on Tuesday claimed responsibility for the attacks but provided no evidence.
Prime Minister Ranil Wickremesinghe said at a news conference he believed the Easter day attacks had links to ISIL, and the government's security agencies were monitoring Sri Lankans who had joined the armed group in Iraq and Syria and returned home.
"We will be following up on IS claims, we believe there may be links," he said.
At least 40 people have been arrested in connection with the attacks and a state of emergency has been imposed, giving police extensive powers to detain and interrogate suspects without court orders.
Among the dozens of the detained were the driver of a van allegedly used by the suicide attackers and the owner of a house where some of them lived.
As a community, we should have some introspection and see how these groups have come into being.
NM Ameen, the president of Muslim Council of Sri Lanka
A prominent Muslim organisation in Sri Lanka said all perpetrators should be brought to justice, adding it was ready to assist the victims of the blasts.
"We do not have information to make a comment about that [the accusations]. But as a community, we should have some introspection and see how these groups have come into being," NM Ameen, the president of the Muslim Council of Sri Lanka, said.
"From what we know, it is a small radicalised Muslim organisation that has caused these devastations. We do not have enough information to say it has global links," Ameen told Al Jazeera.
National day of mourning
On Tuesday, Sri Lanka began a national day of mourning with three minutes of silence for the victims.
More than 500 people have been wounded, including 375 who are still being treated in hospital.
The first mass burial for the victims of bombings that struck churches and luxury hotels took place in Colombo on Tuesday.
|Sri Lankans pray during a three-minute nationwide silence observed to pay homage to the victims of Easter Sunday's blasts outside St Anthony's Shrine in Colombo [Eranga Jayawardena/AP]|
Mourners and relatives of the victims brought flowers to the memorial service and prayed with the clergy as coffins were being carried in and out of the church.
The state defence minister's statement comes a day after Rajitha Senaratne, the health minister and Cabinet spokesman, blamed President Maithripala Sirisena's government for failing to act on intelligence shared weeks before the multiple blasts.
The attacks have underlined concern over fractures in Sri Lanka's government, and whether the discord prevented action that might have stopped them.
The health minister said on Monday that Wickremesinghe had not been informed about the warning and had been shut out of top security meetings because of a feud with President Sirisena.
Sirisena fired Wickremesinghe last year only to be forced to reinstate him under pressure from the Supreme Court. Their relationship is reported to be fraught.
Analysts said the targeting of churches and hotels where foreign tourists stayed in Sri Lanka was a "new and worrying development" in the predominantly Buddhist country.
A senior Asian counter-terrorism official, who declined to be identified, told Reuters news agency the attack was likely carried out by a group with "significant operational capability and skilled commanders".
Four of the bombs went off at roughly the same time at 8:45am, with two others coming within 20 minutes.
Two other explosions rocked Colombo in the afternoon. Authorities later found unexploded devices and a van full of explosives in various locations.
The violence was the worst the country has witnessed since the 26-year civil war between ethnic Tamil separatist rebels and government forces ended in 2009, when deadly bomb blasts were common in Colombo and other cities.
There were fears the attacks could spark a renewal of communal violence, with police also reporting late on Sunday there had been a petrol bomb attack on a mosque in the northwest and arson attacks on two shops owned by Muslims in the west.
Christians, Muslims and Hindus form nearly one-quarter of the island's 23 million population.
Additional reporting by Dilrukshi Handunnetti in Colombo