Visakhapatnam, Nov 7 (IANS): A day after an auxiliary ship of the Navy sank, killing one personnel, navy chief R.K. Dhowan has cut short an international tour, while an official probe has been ordered into the incident.

Admiral Dhowan, who is in the Seychelles to hand over a patrol boat to the island nation, was to stay there till Nov 9.

He is, however, likely to be back in India soon after handing over the vessel to thne Seychelles government.

An official board of inquiry has been ordered in the incident.

"Full scale search and rescue operations are on to find the four missing Navy personnel," a navy official said.

At least eight naval ships and aircraft have been deployed for the search and rescue operation.

Initial reports suggest that one of the compartments of the ship experienced flooding during an operation, causing it to sink, a senior navy official said.

"It could have been due to a problem with the seal material," the official said, adding the exact reason can be ascertained only after the report of the board of enquiry comes.

There were 28 Navy personnel on board the vessel which was on a routine mission to recover practice torpedoes fired by fleet ships during a routine exercise, when it sank.

Twenty-three of the personnel were rescued.

The Torpedo Recovery Vessel (TRV) A-72 sank off the coast of Visakhapatnam around 8 p.m. Thursday.

Built by the Goa Shipyard Limited in 1983, the ship had served the Indian Navy for 31 years.