In the fifth incident involving naval warships in the last six months, INS Betwa has suffered damage in its critical component after which the Navy is carrying out an investigation.
The latest incident detected last week comes six months after INS Sindhurakshak submarine sank in Mumbai harbour following a blast.
The SONAR (Sound Navigation and Ranging) system of warship INS Betwa was detected with hairline fracture in its dome that resulted in ingress of sea water into the system, Navy sources said here.
After the leak was detected in the warship's critical system, it was brought to a dry-dock for inspection. Investigations are being carried out to find out the reasons behind the damage, they said.
The damage was noticed when it entered the Mumbai harbour after returning apparently from anti-piracy operations.
The Mumbai harbour is facing a problem of silting these days and dredging is being done to enhance the depth there. Around the same place last week, INS Sindhughosh submarine was caught in a low tide phase in the waters and had a close shave amid fears of running aground.
The possibility of the SONAR system, which is the lowest point of a warship, getting damaged by hitting some ground object has not been ruled out so far by the Navy.
Defence Minister A K Antony has sought a detailed report from the force on the particular incident but the Navy has not even ordered a Board of Inquiry into it.
After the INS Sindhurakshak sank in August last year, in which all 18 personnel on board were killed, there have been a series of incidents involving naval warships.
A new warship caught fire while it was stationed at the Vishakhapatnam docks and suffered extensive damage. Along with it, there was a fire incident on board the then only aircraft carrier in the force INS Virat.
A fishing trawler sank after colliding with Navy's frontline frigate INS Talwar near Ratnagiri district of Maharashtra injuring four fishermen on board.
The Defence Minister had cautioned the force against frittering away expensive national resources but the Navy Chief stated that compared to other navies, the Indian Navy had a far better safety record.