A Canadian warship on patrol off the east coast of Africa seized the largest quantity of heroin ever discovered by a member of the multi-national maritime task force, according to the Department of National Defence.

HMCS Toronto boarded a ship on Dec. 18 during a patrol in the Arabian Sea and discovered 506 bags of heroin weighing more than 538 kilograms.

The frigate has made a number of drug seizures in the past few months. In October the ship intercepted a suspected drug smuggling vessel and seized 154 bags of heroin weighing more than 180 kilograms.

To date, the ship has recovered approximately 8.22 metric tonnes of narcotics, according to DND.

This seizure marks the largest heroin seizure in the history of Combined Maritime Forces operations, a multinational force combating terrorism across the Red Sea, Gulf of Aden, Arabian Sea and the Gulf of Oman.