[1] The Lamon Bay invasion force consisted of the following ships:[3] The first Japanese detachment to land was the 2nd Battalion of the 20th Infantry Regiment under Lt Col Nariyoshi Tsunehiro at Mauban.

Coming ashore at dawn on 24 December under cover by aircraft provided by the seaplane carrier Mizuho, the Japanese immediately came under attack by the Philippine 1st Infantry, which was dug in on the beach.

The Philippine Army fell back five miles to the west, halting the Japanese advance towards Lucban and the south shore of Laguna de Bay at 1430.

[1] By the evening of 24 December, the Japanese had successfully landed at Lamon Bay, and at the cost of only 84 killed and 184 wounded had completed its encirclement of the approaches to Manila from the south.

General Masaharu Homma, who had a poor opinion of the quality of the IJA 16th Division based on its combat record in China, expressed considerable surprise at the success.

[1] By evening of 24 December, General Homma transferred his staff ashore at Bauang, where he set up the IJA 14th Army HQ in preparation for the final drive on Manila.