Sri Lanka's police chief Friday became the latest senior official to quit over failures to prevent the Easter massacre carried out by an Islamist extremist group, whose top leader died in one of the suicide blasts.

"The IGP has sent his resignation to the acting defence secretary. I'll nominate a new IGP soon," he said.

Jayasundara's resignation came a day after the country's defence secretary Hemasiri Fernando resigned on Thursday. Jayasundara on Friday appeared before a committee appointed by the President to probe the blasts. The committee has been asked to submit its report within two weeks.

President Sirisena had asked both Fernando and Jayasundara to quit after their failure to prevent the blasts despite having prior intelligence.

Thusitha P Wanigasinghe was appointed as the acting defence secretary Friday. He earlier served as an Additional Secretary at the Ministry of Defence.

Top officials have acknowledged that Sri Lanka received intelligence about possible terror strikes ahead of the attacks, but both Sirisena and Prime Minister Ranil Wickremesinghe said that they did not receive the information.

Nine suicide bombers carried out a series of devastating blasts that tore through three churches and three luxury hotels on the Easter Sunday. The Islamic State group has claimed the attacks, but the government has blamed local Islamist extremist group National Tawheed Jamath (NTJ) for the attacks.

The health ministry Thursday night sharply revised the death toll downward to 253, saying the previous figure of 359 was due to a "calculation error".

Sirisena said the intelligence supplied by a friendly nation was not shared with him by officials. "All they have done was to exchange letters among themselves," he said.

"I asked both police chief and defence secretary why the information was not shared with me, they remained silent," he said.

He said the security lapse was also due to the current government's weakening of intelligence operations.

This is a reference to the arrest and trials against a handful of military intelligence officers who were responsible for attacks and murder of journalists, abductions and ransom taking, he said.

He said the power struggle in his government was because he had objected to the government's weakening of the security forces.

Sirisena said he would soon set up a Joint Operations Command to combat terrorism and each and every house would be checked for the safety of all citizens.

The president confirmed that Sri Lankan Islamist extremist Zahran Hashim, the top leader of the NTJ, died in the blast at the Shangri-La hotel.

He led the attack on the hotel and was accompanied by a second bomber, Ilham Ahmed Ibrahim. The president said the information came from military intelligence and was based in part on the CCTV footage recovered from the scene.

Hashim, believed to be 40 years old, appeared in a video released by the Islamic State after the attacks.

In the video, the round-faced radical cleric was seen dressed in a black tunic headscarf and posing with a rifle. He was accompanied by seven masked attackers.

The country's Muslim community had been warning about the firebrand cleric for years. However, it was the ISIS video that provided solid evidence about the Sri Lankan cleric's role in terrorism and the Easter bombings.

Hashim, originally from the east coast region of Batticaloa, was a college drop-out and hailed from an average Muslim middle-class family.

The president also appealed to the island nation not to view its minority Muslim community as terrorists in the wake of the attacks.

Sirisena said despite the attacks, the island's nine per cent Muslim minority must not be regarded terrorists.

"We looked into banning the NTJ but we do not have laws to do that right now. We have to draft new laws. We will get this done soon," he said.

"Information is that around 130-140 ISIS suspects are in the country. Around 70 are arrested, we will arrest them all very soon ending this (terror)," Sirisena said.

Police said that over 70 suspects, including five women, have been arrested as the Lankan authorities have intensified their search operations with the help of the army.

A team of 15 officials of the CID have been formed to investigate the Easter attack, said Police spokesperson Ruwan Gunasekara.

This Friday, some mosques cancelled prayers after Muslim affairs minister called on the community members to pray at home instead, in solidarity with churches that have closed over security fears. Among mosques that did hold Friday prayers in Colombo, attendance was thin.

Security was beefed up around "a certain category of mosques" after intelligence warning that the NTJ was planning an attack on them during Friday prayers.

A letter, signed by DIG Priyantha Jayakody on behalf of Inspector General of Police Jayasundara and dated April 24, warned that a certain category of mosques identified as 'Awliya Mosques' could be possible target.

The city and the immediate suburbs of Colombo looked deserted this morning. Most offices have allowed employees to work from home.

"During the last 24 hours, there have been no incidents reported," Brigadier Sumith Atapattu, the military spokesman, said.

He said the Lankan Army would continue search operations for suspects linked to the terror group.

(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)