PHNOM PENH — Around 1:00 a.m. on April 17, 1975, “two A2-jeeps of Division 3, flying a white flag as a sign of surrender, drove from the Phnom Penh boundary, using a speaker to transmit this recorded message to the population: we all must drop down weapons and begin negotiations…we have to raise the white flag as a sign of peace.” The voice was that of General Lon Nol, president of the Khmer Republic, who had actually left the country a few days earlier.  

At 2:45 a.m., the government soldiers on the front line were told to return to their units’ headquarters to drop off their arms. The war was over, and the Khmer Rouge soldiers were marching into the capital.  

This hour-by-hour account of the Khmer Rouge forces seizing Phnom Penh, and taking control of the country, was given by a Khmer Rouge commander who brought the information over to the Documentation Center of Cambodia (DC-Cam) in the early 1990s.

This commander was overseeing people’s evacuation from Phnom Penh at the Monivong bridge, also known as Kbal Thnal bridge, said Youk Chhang, executive director of DC-Cam.

“The document…has been catalogued [DC-Cam Archives, document number D00710] and used by researchers,” he said. “The details listed show that this operation was very well planned with a clear intention to force people out of the city of Phnom Penh.”

As the commander explained, the Khmer Rouge soldiers were to enter Phnom Penh at 6:15 a.m. by six set routes. Those from the Northern Zone, were to use the newly-built Chroy Changva bridge, those from the Eastern Zone to arrive by the National Road 1, those from the Southwest Zone by the National Road 3, and so on.

Equipped with weapons and in uniform, which was being dressed in black with a cap and sandals made of tire rubber, they were to walk in line on both sides of the road, holding their rifles pointing toward the road, in the direction of Wat Phnom—the Buddhist pagoda set on a hill in the middle of the capital.
 

At 7:15 a.m., an announcement was made on a radio station to the effect that the Khmer Rouge had defeated the Cambodian government forces and had taken control of the capital. The message stressed that, as the Khmer Rouge commander pointed out, “our party obtained this victory at gunpoint…Our party does not need to negotiate with any individual or party.” No meeting was to be held with government officials to negotiate any terms of their surrender, the commander said.

By 7:45 a.m., Khmer Rouge soldiers started patrolling the city’s streets and alleys, telling people that they had to immediately leave the capital. This was not negotiable, the commander said.  “Anyone who refused to move would be shot dead,” he said.

“The communist party intended to kill people considered to be untrustworthy, such as former civil servants and soldiers, preventing the local public and international opinions from observing their acts on the basis of a slogan: try not to make waves while dragging the boat, and not to contaminate the water while catching fish,” the commander said.

Evacuating the cities was crucial, explained French historian Henri Locard who has researched and written on the Khmer Rouge regime for decades and testified at the Khmer Rouge Tribunal during which the regime’s top leaders were put on trial—it ended in December 2022, with three convictions.

“They decided to evacuate the cities twice,” Locard explained, “[starting with] a first meeting in 1974…They had evacuated a number of cities,” he said, as they were taking control of the country, defeating the government army. “This had been a success…They thought this was a wonderful strategy because it was enabling them to control the population,” he said.

Then 15 days before the fall of Phnom Penh, there had been a meeting during which the Khmer Rouge leaders had voted to evacuate the capital. “Because they could not control Phnom Penh,” Locard said. “They did not have enough people to do so…There were between 20,000 and 40,000 Khmer Rouge and the population of Phom Penh was between 2-to-3 millions.”

Since the start of the war between the Khmer Rouge and the Cambodian government forces in 1970, a large number of people from other parts of the country had taken refuge in Phnom Penh, increasing its population and making it harder to control. Still, Locard said, “no one had ever dared empty cities in modern times.”

From 7:30 a.m. on, the Khmer Rouge commander said, Khmer Rouge soldiers crisscrossed the capital in a car, announcing via a loudspeaker: “don’t panic…Be prepared for moving out of the city for a short period of time, maybe three days…No need to bring along too many things…Don’t walk in any direction opposed to what the Angkar [organization] has set.”  
 

Still, the Khmer Rouge did not immediately achieve full control of the capital. As U.S. photographer Al Rockoff explained during his testimony at the Khmer Rouge tribunal on Jan. 28, 2013, he first realized that the Khmer Rouge had entered the city around 8:00 a.m. when he saw Khmer Rouge soldiers march toward Wat Phnom, coming from several directions.

“I spent the next two hours, three hours, going through parts of the city hitching a ride with the Khmer Rouge,” he said. “It was easy to travel around in the first hour. I got as far as the Independence Monument, and then I went back to the intersection of Monivong and Sihanouk Boulevards, where I stayed nearly an hour.

“I photographed the collection of weapons, the disarming of soldiers, a large group of soldiers traveling under guard being sent towards the Olympic Stadium,” Rockoff said. Although he had no proof, he believed that the Khmer Rouge were killing the soldiers in the stadium.

In the city, he said, “I did not see people executed or the signs of their being executed, but you could smell the sites of execution if the wind blew the right way. You could get whiffs of it.”

Rockoff was eventually told to go to the French Embassy where foreigners and also some Cambodians, including a few government officials, had taken refuge. Most Cambodians would later be ordered by the Khmer Rouge to leave the premises.

A couple of weeks later, all people at the embassy were taken to the Thai border by trucks. As Rockoff explained, the drive to the border took far longer than it should have. The Khmer Rouge used specific roads, making sure the journalists and people taken out of the country would not see what was happening, he said.

After the Khmer Rouge were ousted from power in January 1979, it would take a long time before the extent of the killings and deaths during the regime—more than 2 million people—would be known.