Exchange of firing between security forces and militants, involved in PNS Mehran attack, is still continuing almost eight hours after the attack began.
According to the sources, fresh commandos have reached PNS Mehran on Monday morning and its Zarar company is participating in the operation while helicopter are also being used for surveillance.
Fifteen bomb explosions have been heard so far since militants assaulted PNS Mehran.
Navy spokesman said that two P-3C Orion aircrafts have completely destroyed in the attack while five including four navy and one rangers personnel have been killed while nine others received injuries.
He expressed hope that operation would soon be concluded.
