Passage: Operation Eagle Pull was the United States military evacuation by air of Phnom Penh, Cambodia, on 12 April 1975. At the beginning of April 1975, Phnom Penh, one of the last remaining strongholds of the Khmer Republic, was surrounded by the Khmer Rouge and totally dependent on aerial resupply through Pochentong Airport. With a Khmer Rouge victory imminent, the US government made contingency plans for the evacuation of US nationals and allied Cambodians by helicopter to ships in the Gulf of Thailand. Operation Eagle Pull took place on the morning of 12 April 1975 and was a tactical success carried out without any loss of life. Five days later the Khmer Republic collapsed and the Khmer Rouge occupied Phnom Penh.

Question: What country was the US leaving from in operation Eagle Pull?
Cambodia