Defence Ministry Secretary Kamal Gunaratne says it is wrong to claim that perpetrators of the Easter Sunday attacks are being protected due to some "secret deal".

"There is no secret deal. Investigations are being carried out properly," Gunaratne said while speaking to a private TV station.

"After the current government came to power, 42 persons were remanded in connection with the Easter Sunday attacks. 88 people are currently under Detention Orders. But, arresting or taking into custody is not sufficient. We must gather evidence to prosecute and convict them before the court of law and this process takes time," he added.

"We cannot let a terrorist go scot free due to the absence of evidence. So, taking some time to gather evidence is not a deal. This heinious terrorist attack was carried out by a group of people who misinterpreted a great religion," Gunaratne added.