Short answers, pulled from the story.
The Malayan Emergency began on the 17th of June 1948, following the killing of three European plantation managers at the Elphil Estate near Sungai Siput. The Malayan government officially declared the state of emergency over on the 31st of July 1960, though a second phase of insurgency began in 1968 and lasted until the dissolution of the Malayan Communist Party in 1989.
The British used the term "Emergency" rather than "war" to avoid triggering insurance exclusions. London-based insurers would not pay out in instances of civil wars, so designating the conflict an emergency protected British business interests in Malaya.
The Malayan Communist Party and the MNLA were led by Chin Peng, a veteran anti-fascist and trade unionist who had previously played an integral role in the Malayan Peoples' Anti-Japanese Army's resistance against Japanese occupation. After the emergency ended, Chin Peng left southern Thailand for Beijing, where he was housed by the Chinese authorities in the International Liaison Bureau.
The Batang Kali massacre occurred in December 1948, when twenty-four unarmed civilians were executed by the Scots Guards near a rubber plantation at Sungai Rimoh in Selangor. All victims were male, their village was burned to the ground, no weapons were found, and the only survivor was a man named Chong Hong who survived by fainting and being presumed dead. The British colonial government staged a coverup of the killings, and the British government agreed to investigate only in 2009.
The Briggs Plan, implemented after General Sir Harold Briggs was appointed to Malaya in April 1950, aimed to cut the MNLA off from its civilian support base by forcibly relocating one million rural civilians, roughly ten percent of Malaya's population, into six hundred barbed-wire camps called "new villages." The plan also targeted the MNLA's food supply by destroying crops grown in jungle clearings and restricting provisions from rural communities.
Britain became the first nation in history to use herbicides as military weapons during the Malayan Emergency. A compound called Trioxone, virtually identical in composition to the later Agent Orange and likely carrying heavier dioxin contamination, was sprayed over 1,250 acres of roadside vegetation between June and October 1952, then used again from February 1953 to destroy food crops grown by communist forces. US Secretary of State Dean Rusk later advised President Kennedy that Britain had established the precedent for herbicide warfare in Malaya.