The Daily News quoted Justice Minister Rauf Hakeem as saying that the end of emergency rule, announced by President Mahinda Rajapakse last week, would lead to the immediate release of suspects detained under the regulations.
"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 secu