Crew members of the possible North Korean spy ship that sank in the East China Sea after firing on Japanese patrol boats over the weekend also launched rockets during the shootout, the Japan Coast Guard said Monday.

Images captured by an infrared camera show two or three of the unidentified ship's crew using shoulder-mounted launchers to fire rockets at the Inasa and the Amami, two coast guard patrol vessels.

The rockets missed their targets, coast guard officials said, adding that red flames were seen passing above the boats. Coast guard officials said they believe the rockets were fired almost simultaneously.