The French ministry of defence said it was acting on information from Frenchcustoms about the 1,500-dwt Luna-S (built 1974), flagged in Tanzania.
All eight seafarers were evacuated safely
Algerian vessels helped isolate the blaze in the accommodation block asthe ship drifted.
Customs officials later confirmed the presence of cannabis on board, butwork to search the vessel and estimate the volume involved has been slowed byheat and smoke
A tug is towing the vessel, operatedby Zain Shipping of theMarshall Islands, into a French port.
News of the incident comes days after anotherTanzanian-flagged ship, the 2,100-dwt Gold Star (built 1975), was interceptedoff Italy with 30 tonnes of cannabis on board.
Its crew had set fire to the illegal cargo, before jumping intothe sea.
The vessel islisted as operated by Gold Star Shipping of the Marshall Islands.