[2][3] About 03:00 on 8 December 1941, the 2nd Battalion, 143rd Infantry Regiment, 55th Division of the Imperial Japanese Army, under the command of Major Kisoyoshi Utsunomiya, began landing troops at Prachuap Khiri Khan.

When informed of the invasion, Wing Commander Mom Luang Prawat Chumsai of Kong Bin Noi (Squadron) 5 immediately gave orders to resist.

The small garrison of pilots and ground crew was reinforced by members of the constabulary and the Yuwachon Thaharn (a quasi-military teenage auxiliary) who had managed to escape from the town of Prachuap Khiri Khan after the Japanese captured the telegraph office and the police station.

Flying Officer Man Prasongdi took off in a Hawk III armed with four 50 kg bombs and attempted to attack Japanese transports in Ao Manao harbor, but he could not locate them due to heavy fog and rain.

The Thais smashed the instruments of the isolated airfield control tower and set fire to it, as the runways were abandoned.

Pilot Officer Somsri Suchrittham and his men, whose strength was now around thirty, were forced to withdraw when their northern flank was threatened by the abandonment of the runways.

Having successfully secured the beachhead, the Japanese proceeded to occupy what was left of the hangars and runways, and reinforcements, including artillery and ten tanks, were landed from the transports.

The following morning, the exhausted Thais received a telegram from the Ministry of the Interior, brought in by a postman during a lull in the battle.

It contained a number of Thai government officials, including the provincial undersecretary, Jarunphan Isarangun na Ayutthaya.

Jarunphan handed Wing Commander Prawat a direct order from the Prime Minister, Field Marshal Phibunsongkhram, telling him to cease resistance immediately.