The president's move comes days after the island nation was rocked by a series of terrorist bombings on Easter Sunday, despite reported intelligence reports suggesting the possibility of such an attack. Citing sources, the Daily Mirror on Wednesday reported that the president had informed the two officials this morning. It was also reported in the afternoon that the Defence Secretary had met the President a short while ago at the presidential secretariat.

On Tuesday night, in his first address to the nation since the attacks, President Sirisena announced that major changes were likely to take place in the nation's security apparatus within 24 hours.

"I will completely restructure the police and security forces in the coming weeks. I expect to change the heads of the defence establishments within the next 24 hours," Sirisena said in a special address to the nation.

Sirisena, however, denied the allegation made by some political leaders that he'd had prior knowledge of warnings given by other countries of a possible terrorist attack, or the one issued by local intelligence agencies.

"Why did the police not act on intelligence is today the burning question — I want to state here that I was not informed either. Had I been informed, I would have acted immediately," Sirisena stated in a televised address to the nation.

On Tuesday, Daesh in Arabic language claimed responsibility for the bomb blasts in churches and hotels in Sri Lanka. However, the militant group did not provide any substantial proof of the claim.

Earlier in the day, Sri Lanka's Minister of State for Defence Ruwan Wijewardene acknowledged that security lapses were behind the serial blasts that killed at least 359 people as of Wednesday morning, including dozens of foreigners.

Wijewardene said the investigation was continuing and authorities expected to make further arrests in the coming days. "We can firmly say in the next couple of days our security agencies will have the situation in this country firmly under control," he said.

Ruwan Wijewardene, who previously said the attacks were carried out by the local jihadi group National Thawheed Jamaat (NTJ), said on Wednesday that it was not the NTJ but a splinter group which is behind the attack.

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