Mr Tarit, a member of the CMPO, said Mr Sonthiyan is currently being detained on a charge of violating the emergency decree.
Although the court has ordered his release on Feb 17, Mr Sonthiyan is still wanted for insurrection under Section 113 of the Criminal Code.
The CMPO would on Feb 15 file treason charges against him and ask for court permission to detain him for 12 days at a time, and seek extensions, said Mr Tarit.
He said the insurrection charge carries a heavier penalty than breaking the emergency law.
The court will decide whether to release him on bail, Mr Tarit added.