An anchor handling tug supply vessel owned by Shipping Corporation of India, 2011-built SCI Ratna , sunk last night around 175km off Mumbai.

The vessel made a distress call around 5:27pm local time and by 5:55pm the crew was being assisted by offshore support vessel Greatship Prachi. All 15 crew members were rescued and watched their vessel sink.

The Indian Express reports that flooding in the main engine room was what led to the incident, and that the Indian Coast Guard would start investigations today.

“We are in touch with the authorities concerned and have been appraised about the rescue operations. We are still trying to get details on the movement of the ship since it was an offshore vessel whether it was returning from the oil rigs or was ferrying any material to the rigs. The nature of the cargo on board the vessel is also a major point of concern for us. However, we would be able to assess if there has been any oil leak only in daylight,” a senior official from SCI told The Indian Express.