COLOMBO • A state of emergency was extended by Sri Lanka's President yesterday, with the move seen as going back on pledges to relax the tough laws introduced after the Easter Sunday attacks that killed 258 people.

President Maithripala Sirisena said in a decree that he believed there was a "public emergency" in the country and was invoking provisions of the public security Act to extend the state of emergency.

The tough laws, granting sweeping powers to police and security forces to arrest and detain suspects, were due to expire yesterday.

Just over 100 people, including 10 women, are in custody over April's suicide attacks on three churches and three luxury hotels in Colombo.

Late last month, Mr Sirisena told diplomats from Australia, Canada, Japan, the United States and European states that the security situation was "99 per cent back to normal" and he would allow the emergency laws to lapse by June 22.

He assured the diplomats that security forces had either detained or killed all those directly involved in the attacks, blamed on local extremists and claimed by the Islamic State in Iraq and Syria terror group.

There was no immediate word from the government on why Mr Sirisena changed his mind, but security remains tight in the capital.

The emergency can be declared for a month at a time, and Parliament must ratify it within 10 days.

The continuation of the emergency came as police announced criminal investigations against several top officers, including the Inspector-General, for negligence and lapses ahead of the bombings.

Mr Sirisena himself has been criticised for failing to act on precise Indian intelligence that terrorists were about to hit Christian churches and other targets in Sri Lanka.

A parliamentary public inquiry has been told that Mr Sirisena - who also holds the defence and law and order portfolios - failed to follow proper national security protocols.

The mainly Buddhist nation of 21 million people was about to mark a decade since ending a 37-year-long Tamil separatist war when the extremists struck.

AGENCE FRANCE-PRESSE