This was a British naval sweep against Japanese coastal shipping in the area to the north of Gwa in the Arakan western coastal region of Japanese-occupied Burma (9/12 November 1944).
The undertaking involved the motor launches ML-412, ML-413 and ML-419 , operating from the Naf river, between Gwa and Cape Negrais. The search was without incident until 17.20 on 10 November, when the launches were circled by a Mitsubishi Ki-46 ‘Dinah’ reconnaissance aeroplane, which kept well out of range. It was thought unlikely that the Japanese would be able to issue a warning in time to stop any coastal shipping which might be leaving Bassein after dark, so the plan remained unchanged. At 18.00 the launches changed course to close the coast, and at 20.00 reached a position some 5 miles (8 km) to the south of Cape Negrais and began to follow the coast northward. By 04.20 on 11 November the launches were 1 mile (1.6 km) to the west of Gwa island. The harbour entrance was closed but no ships were seen, and course was therefore shaped for base.
At 12.13 the launches were attacked by two Kawasaki Ki-48 ‘Lily’ light bombers. The first aeroplane attacked from the starboard quarter and straddled ML-419 with two bombs, then circled and attacked again from the port beam, one of its bombs exploding on the port side of the launch and the other bouncing on the launch but failing to explode. Meanwhile the second aeroplane attacked ML-412 from the port bow, dropping two bombs which landed 20 yards (18 m) off but did not explode. The aeroplane also strafed the launch and then missed the stern of ML-413 to drop a bomb in her wake. The attacks were pressed home at sea level with great determination and were based on skip bombing technique. During the attack one of the aircraft was repeatedly hit by ML-412 and ML-413 and the other by ML-419 and ML-412, and was seen to crash into the water off the launches’ starboard quarter, while the other departed with smoke pouring from its starboard engine.
During the engagement Lockheed P-38 Lightning fighters of the USAAF arrived, chased the damaged Japanese bomber and shot it down.