NEW DELHI, Dec. 5 (Xinhua) -- At least two Indian sailors were killed while 14 others injured in a naval warship mishap at Mumbai dockyard Monday, a defense official said.

"The mishap took place when Indian Navy's INS Betwa, a guided missile frigate, tipped over while undocking in Mumbai," Indian Navy's spokesperson D.K. Sharma told the media.

"The incident actually occurred during undocking evolution wherein it is suspected that dock blocks mechanism failed."

The 3,850-ton INS Betwa is one of India's important naval assets and one of the principal warships of the Western Naval Command, armed with anti-ship missiles, surface-to-air missiles and torpedoes.

INS Betwa was used in the rescue of Maldivian hostages in 1988 and it also participated in the evacuation of Indian citizens from Lebanon to Cyprus in 2006.