Sri Lankan President Maithripala Sirsena on Friday said there are around 140 suspects believed to be linked to IS in the country.
Addressing a media conference in Colombo, Mr Sirisena said, many of them have been arrested and a hunt is on for the rest.
He said, country security forces are capable of wiping out terrorism from the country and restore normalcy soon.
The President said, highly deive information was given by a friendly Nation to a Head of Intelligence on April 4th and it included targets & methods of the Sunday attack.
He said, until the 12th of April, this information was passed around and action will be taken against all officials who neglected their duties.
Mr Sirisena asserted that a total reorganization of the security establishment will take place in the days to come.
Srilankan President said close relationship between drug trafficking and extremism, efforts to eradicate drug trade may have been a reason for bomb attacks.
He said the armed forces and intelligence setup was weakened over past years and it was one of the main reasons for his rift with the Government. Mr Sirisena added that top intelligence officers were harassed and he had to even send a few on overseas appointments to help them. Mr Sirisena called upon the Sri Lankan people to not look at the Muslim community as terrorists and they must protect them.
Meanwhile, security remains tense and police crackdown on suspects continue. Police issued an appeal for information on three women and one man suspected of involvement in the attacks.
The U.S. embassy in Colombo in a message said terrorist groups continue plotting possible attacks in Sri Lanka. Few countries including Britain and Israel have issued travel advisories against travel to the country in wake of the security situation. Earlier, the government had revised the death toll in Sunday attacks to 253, from 359 reported earlier.