A Canadian frigate patrolling in the Arabian Sea has made a massive drug bust, seizing over four tonnes of hashish from a Pakistani vessel last week.

The HMCS Charlottetown's commanding officer Cmdr. Patrick St-Denis, told Â鶹´«Ã½net via phone that his ship began tracking a vessel with suspected ties to terrorism on Feb. 18.

"We were able to track the vessel just outside Pakistani water and were able to get a boarding party on board," St-Denis said.

He said that the Pakistani fishing vessel's 11-man crew was very co-operative at first. But after six hours on the vessel, the Canadian boarding crew found sacks of hashish in the fuel tanks and under the deck plating. 170 sacks weighing 4.3 tonnes in total were found in total.

"They were quite upset that we found something," St-Denis said of the fishing vessel's crew. He said that the information on the crew's suspected links to terrorism is classified.

The boarding and seizure took 17 hours in total. The hash was dumped into the ocean by the Canadian crew and Pakistani maritime security forces apprehended the fishing vessel after the Canadians left.

"We are very proud and Canadians should be proud of the operation we are conducting here," St-Denis said.

HMCS Charlottetown is part of a combined task-force working in the Persian Gulf region in support of anti-terrorism operations. The ship is based out of Halifax, N.S.