Jeyanthan Tharmalingam, 35, went last Thursday to give a statement in a case about illegal employment in which he was a victim, at a police station in the eastern suburbs of Paris, judicial sources said.
But police quickly realised he was the subject of "an international arrest warrant for terrorism", a police source said on condition of anonymity.
He appeared before a Paris court where he was notified of the warrant against him before being released on bail.
Tharmalingam is alleged to be a member of the Liberation Tigers of Tamil Eelam which waged a 37-year long separatist war that left at least 100,000 dead, according to UN estimates, and was defeated by the army in 2009.
He is listed on the Interpol website as wanted for terrorism.