Police officials in Karachi said a First Information Report registered at Sharah-e-Faisal police station quoted Lt Irfan Asghar who was on duty when PNS Mehran was attacked as saying that 10-12 terrorists attacked the airbase.
The FIR was registered under the Explosives Act and Anti-Terrorism Act.
Malik had told reporters yesterday that six terrorists were involved in the attack that left 10 security personnel dead and 15 more injured.
Malik said at least four attackers were killed or blew themselves up while two were believed to have escaped after the brazen assault.
Naval chief Admiral Noman Bashir too told the media that four attackers were killed.
The FIR filed by the navy stated that the terrorists entered the airbase by scaling walls near a check post.
Two suicide vests, eight grenades, four Kalashnikovs and a rocket launcher were recovered from the dead attackers, police told the media.
There has been considerable confusion regarding the number of terrorists involved in the attack on PNS Mehran, the Pakistan Navy's main naval air station.