Some elements of the government have known for weeks about warnings about a possible attack on churches and tourist destinations.
At the beginning of April, intelligence agencies in India and the US warned Sri Lanka about the threat, the authorities said. A memo written by Sri Lankan security officials was so specific that there was even a list of suspects. In the run-up to the holiest day in the Christian calendar, the warnings of frequency and urgency seemed to increase.
But no one made a difference.
When suicide bombers arrived in three churches in Sri Lanka and three upscale hotels in Colombo, none of them faced increased security. As the worshipers closed their eyes in prayer as the hotel guests dined in for breakfast, the attackers set their equipment alight ̵
Now there are fears that the political feuds would have given a window to a catastrophic collapse that resonates throughout the region. 19659002]
The origins of a seemingly spectacular safety failure go back more than two weeks. According to government spokesman Rajitha Senaratne on April 4, foreign international intelligence agencies told Sri Lankan officials that they could launch suicide attacks against Christian churches and tourist attractions.
Five days later, on April 9, the country's Ministry of Defense informed the Inspector General of Police of this alleged conspiracy, naming a group suspected to be behind the plan, the nation of Thawahid Jaman (NTJ). Unusually, the memo also contained a list of suspects.
On April 11, another memo signed by Priyalal Dissanayake, Deputy Inspector General of Police, was distributed to a number of security services and some ministries, and a police source, according to Senaratne. This memo, from which CNN had seen a copy, was the threat and again included a list of suspects.
Foreign security services repeated their warnings in the days and hours prior to the attack, Senaratne said. A warning had come ten minutes before the blast, he claimed – though it was not clear if he spoke with precision.
The Economics Minister Harsha de Silva told CNN's Christiane Amanpour that international warnings were "something terrible" "came from the US and neighboring India.
All this happened against the background the divisions within the government that resulted from the constitutional crisis of 2018. In his interview with CNN, De Silva said the prime minister was "in the dark" because of the warnings.
Senaratne, who is also health minister, said the prime minister was Even after the attack, members of the National Security Council refused to attend a meeting convened by the Prime Minister, Senaratne claimed, "I think that this is the only one Country of the world is where the Security Council does not want to come, if he is from the Prime Minister he is called up by the country, "he said.
Regarding the warnings of NTJ involvement in a potential attack, Senaratne said he did not believe a local group would have acted alone. "There has to be a broader international network behind it," he told reporters.
In a statement reported by Reuters, President Sirisena said the Sri Lankan government would seek foreign aid as it investigated possible international links to the attack. Reuters said his office will not comment on the apparent failure to ignore warnings.
De Silva, an ally of the Prime Minister, argued that the terrible loss of Sunday was not a failure of intelligence but a failure to provide an appropriate response to the intelligence services.
Focus on Islamist group
The group mentioned in the memos as planning an attack, Nations Thawahid Jaman, has so far only acted marginally, blaming little more than blemishing Buddhist statues ,
According to Saroj Kumar Rath, a terrorism and security expert at the University of Delhi, NTJ originated in the southern Indian state of Tamil Nadu in the early 2000s.
Manoj Joshi, Observer at Indian Think Tank Observer The Research Foundation said that NTJ had carried out protests in places such as liquor stores in the past, but did not know that terrorist attacks had occurred previously.
There are numerous small groups like the NTJ in India and South Asia, said Joshi. "The problem was that this group did not have any kind of violence (violence) in the past and they (the authorities) may have been blinded by the lack of focus on this group," Joshi said, noting that during Sri Lanka was no stranger to terrorist attacks, historically there was violence in a very different context.
Muslim groups have said they have been trying to warn the Sri Lankan authorities of the potential danger posed by the NTJ. His relative ambiguity, however, raised the question of whether he could have carried out such a sophisticated and coordinated attack on his own.
Dhruva Jaishankar, a foreign affairs officer at Brookings India, told CNN that this was too early speculation about which organizations could have been involved, the role of a "larger organization can not be dismissed".
"It is a bit boring for such an organization to perform complicated simultaneous explosions," he said of NTJ.  Jaishankar said it was known that ISIS groups existed in neighboring India, the Maldives and Bangladesh, Pakistan and the Philippines. However, there are few signs of ISIS activity in Sri Lanka.
What Jaishankar seems to realize is that the attack was religiously motivated and targeted at foreigners. "These are people who wanted to hurt Sri Lanka's reputation," he said.
The coordination and planning of Sunday's attacks, involving several high-profile targets, suicide bombers and powerful bombs, seems to have been intense and must have been in progress for a long time.
The Sri Lankan authorities have already admitted having missed several warning signs. Now, a nation that is still hovering with horror at the bloodshed on Sunday is waiting to see how widespread the failure was and what role its dysfunctional policy played in it.
Jonny Hallam and Kara Fox of CNN contributed to this report.