Sri Lanka's Defence Secretary Hemasiri Fernando resigned over his failure to prevent the Easter terror attacks even as the health ministry sharply revised the death toll downward to 253, saying the previous figure of 359 was due to a "calculation error".
Lankan Prime Minister Ranil Wickremesinghe said authorities were targeting the "sleepers" who could trigger another round of bombings as police released photos of six suspects, including three women, wanted for their involvement in the attacks and sought information regarding them from the public.
Authorities earlier said nine bombers, believed to be members of a local Islamist extremist group called National Thowheed Jamath, carried out the blasts that killed 359 people and wounded more than 500 others.
However, in an embarrassing revision, Dr Anil Jasinghe, Director General of the Health Services, said the larger death toll was released as a result of a calculation error.
"The approximate total of the dead would be 253 and not 359 as reported in media," he said in a statement.
Defence Secretary Fernando handed over his resignation letter to Lankan President Maithripala Sirisena on Thursday. Sirisena had asked Fernando and Inspector General of Police Pujith Jayasundara to quit after their failure to prevent the blasts despite having prior intelligence.
Facing public criticism for not acting against Islamist extremist groups in the island nation, Lanka's Prime Minister Wickremesinghe said some of the suspected attackers responsible for the Easter bombings were being monitored by the country's intelligence services.
But authorities did not have "sufficient" evidence to place the suspected attackers in custody prior to the attacks, he said.
Top officials have acknowledged that Sri Lanka received intelligence about possible terror strikes ahead of the attacks, but both Sirisena and Wickremesinghe have said that they did not receive the information.
Wickremesinghe told CNN that he did not rule out the possibility of more attacks in the country. He said authorities were now focussing on "sleepers" - terrorists who could activate another round of attacks.
"Police and security forces are rounding up those involved, but they're also rounding up the sleepers, those used on second and third rounds (of attacks)," he said.
"The danger has come down drastically, (but) we do have to pick up some more sleepers, which we will do in the next few days."
He said security services were acting out of an abundance of caution, and that should even one militant slip through the net, the damage could be widespread.
"It is a precaution that we are taking, we want to be sure we have everyone in," Wickremesinghe said. "They are worried that one or two could get into a church -- (even) one person can do a lot of damage."
The Lankan authorities have intensified their search operations with the help of the army and arrested 16 more suspects. Officials said that with the fresh arrests, the total number of suspects under their custody has risen to 76.
Lankan President Sirisena has said that 139 people have been identified as suspects in connection with the attacks.
Addressing an all-party conference, Sirisena said that a Combine Operation Centre will be established within the defence ministry for the enforcement of the country's security measures from Friday.
Many of the arrested people have suspected links to the NTJ, the group blamed for the bombings. However, the NTJ has not claimed responsibility for the attacks. The Islamic State has claimed responsibility for the attacks.
Meanwhile, security has been beefed up around "a certain category of mosques" after intelligence warning that the Islamist extremist group blamed for the Easter blasts was planning an attack on them during Friday prayers.
Lanka police chief resigns
Sri Lanka's police chief resigned from his post on Friday, two days after Lankan President Maithripala Sirisena asked him to step down over the security establishment's failure to avert the deadly Easter bombings.
Sirisena, who is also the defence minister, said Inspector General of Police Pujith Jayasundara resigned over failures which led to the attacks on three hotels and three churches on Sunday that claimed 253 lives.
"The IGP has resigned. He has sent his resignation to the acting defense secretary. I'll nominate a new IGP soon," the president said.
The police chief's resignation came a day after the country's defence secretary Hemasiri Fernando handed over his resignation letter to the president.
Sirisena had asked Fernando and Jayasundara to quit after their failure to prevent the blasts despite having prior intelligence.
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.