She broke up and sank in 1982 in the Bulgarian waters of the Black Sea, 40 nautical miles (74 km) south-south east of the Cape Kaliakra at a depth of 1,400 metres (4,600 ft) after a mysterious explosion.

This action resulted in a thorough inspection of the ship's wreck by independent survey teams, employed by the insurance company from Lloyd's Register, Japan.

[2] The rescue operation was coordinated from the Bulgarian shore and involved eight Romanian ships, Motru 25,000 t DWT, Tg.

The sister ships were as follows: M/T Independența (Independence) - collided in 1979 with a freighter at the southern entrance of Bosphorus, Turkey and exploded.

Iris Star lost power because of engine failure during a passage through the Bosphorus on 27 July 2000, and drifted towards Kandilli point.

M/T Libertatea (Liberty) - had the same history (including ownership) as her older sister M/T Biruinţa with the only exception that the ship is still in operation under the name M/T Histria Prestige.