On 27 December, in an effort to prevent the capture of RAF Kuala Lumpur, the 11th Indian Infantry Division occupied Kampar, which offered a strong natural defensive position.

In doing so they were also tasked with delaying the advancing Japanese troops long enough to allow the 9th Indian Infantry Division to withdraw from the east coast.

This jungle-covered mountain offered a clear view of the surrounding plains covered with open tin mining sites and swamps.

Allied forces knew that if the 5th Division of the Imperial Japanese Army captured Kampar, they would also be able to use it as a foothold into the Kinta Valley.

After the loss of Kedah province the 12th Indian Infantry Brigade (Malaya Command reserve force and well trained in jungle warfare) replaced the 11th Division and commenced a very successful fighting withdrawal to the Kampar position, inflicting heavy casualties on the Japanese spearhead units.

The intact and relatively fresh 41st Infantry Regiment (about 4,000 strong) from Major General Saburo Kawamura's 9th Brigade spearheaded the attack on Kampar Hill.

On the 31 December Kawamura launched probing attacks on the 28th Gurkha Brigade's position on the right flank near the town of Sahum with a battalion from Watanabe's 11th Regiment.

On midnight of New Year's Eve the commander of the 155th Field Regiment, Lieutenant Colonel Augustus Murdoch, "ordered a twelve gun salute to be fired at the Japanese".

The well concealed and dug in 15th/6th Brigade, supported by the 88th (2nd West Lancashire) Field Artillery, held on to their positions throughout the two days of fierce fighting on the western slopes of Kampar Hill without relief.

This half company under the command of Captain John Onslow Graham and Lieutenant Charles Douglas Lamb (both officers were from 1/8th Punjab) fixed bayonets and charged the Japanese position.

Graham was rushed to the army hospital at Tanjung Malim where he died of his wounds a day later and was subsequently Mentioned in Dispatches for his actions on Thompson Ridge.

Once Telok Anson had fallen the 3rd Cavalry and 1st Independent Company fell back to the 12th Brigade which successfully delayed the Japanese from taking the main north–south road.

The 12th Brigade covered the retreat of 11th Division and the British pulled back to the next prepared defensive position at Slim River.

Over the four-day period, between 30 December 1941 and 2 January 1942, the 11th Division managed to fight off determined Japanese attacks and inflicted heavy casualties upon them.