ST. JOHN'S, N.L. -- The federal Department of Fisheries has confirmed that yet another North Atlantic right whale has been found dead in the Gulf of St. Lawrence.

In all, the carcasses of 10 of the endangered mammals have been found in the Gulf since June 7.

The most recent find was reported Tuesday from the west coast of Newfoundland, though it remains unclear when the whale was first spotted.

The department issued a statement on Twitter saying the "unprecedented number of right whale deaths is very concerning."

Four of the dead whales were found on the west coast of Newfoundland, but the department says two of them are not among the eight previously identified carcasses.

North Atlantic right whales are critically endangered, with only about 525 believed to be alive.