"Twelve hundred former LTTE members will be released soon," Hakeem told the paper without adding further details.
When the guerrillas were defeated in 2009, the Sri Lankan government said it was holding about 12,000 members of the rebel Liberation Tigers of Tamil Eelam.
Some of the suspects have been freed in the past two years and it is not known how many remain in custody.
The government allowed the state of emergency to lapse on Wednesday last week, but the Prevention of Terrorism Act -- which allows security forces to detain suspects for long periods -- will remain in force.Emergency laws were first imposed in 1983 when Tamil rebels escalated their violent campaign for an independent state for the island's ethnic Tamil minority.
The laws, which gave security forces sweeping powers of arrest, were renewed on a monthly basis with only brief breaks.
The decision to end emergency rule comes ahead of next month's United Nations Human Rights Council meeting in Geneva which is expected to discuss alleged war crimes during the last stages of the ethnic conflict.
The United States has been leading international calls for an investigation into alleged atrocities on both sides as a massive military offensive finally crushed the rebels.
Sri Lanka has so far managed to stave off censure from UN bodies, thanks to the support of allies China and Russia.
Rights groups say tens of thousands of civilians perished in the final months of fighting, while the UN has noted "credible allegations" of war crimes committed by both sides.
Colombo has steadfastly denied any wrongdoing and resisted foreign calls for a probe.