The unrest in academic circles that had bubbled beneath the surface of Cambodia’s civil war surfaced in March 1973 when teachers and students waged strikes that, ultimately, ended in bloodshed.

On March 17, a day before the bombing of US-backed Marshal Lon Nol’s presidential palace, a bloody grenade attack killed two students at the Faculty of Pedagogy in Phnom Penh.

The incident is one of many from the Khmer Republic era on which anti-secrecy website WikiLeaks has shed new light with the release of the “Kissinger Cables” this week.

As Khmer Rouge insurgents closed in on the capital and Nol’s ailing regime contended with food and electricity shortages, the teachers and students became vocal on issues ranging from governance to petrol prices.

In a cable written on March 17, 1973, then-US ambassador Emory Swank described an early report of the bloodshed.

“Fighting broke out at approximately 11:45 this morning at the Faculty of Pedagogy where striking teachers were holding a mass meeting,” he wrote.

According to the intelligence provided to Swank, three civilians had beaten up a teacher and were then tied up.

Just when the situation was calm, “hand grenades began exploding and about 50 persons in civilian dress attacked the faculty, asking where they could find the three detainees”, Swank wrote.

“Preliminary reports indicate two killed and four seriously injured. The two dead are students.”

The US Embassy had been keeping a close eye on the strikes, which had shown signs of abating days earlier.

“On March 6, the government responded to the demands of striking teachers in a ‘decision’ signed by Prime Minister Hang Thun Hak,” Swank wrote in earlier correspondence. “The government declared that it was taking measures to stop illegal price increases, resolve the problem of salaries, prevent the importation of unnecessary products, increase revenue, and institute a policy of austerity.

“[The government] asked that the teachers return to work in the higher interests of the nation.”

The teachers refused, and in coming days, Thun Hak announced a 16-point strategy to appease them.

According to the cables, one person was shot dead in Kampot on March 12 in the presence of  governor Ung Nhach.

This occurred a day after the governor had ordered troops to shoot down anti-government banners hanging from a school where teachers had been barred from striking.

“The teachers claim that two innocent bystanders were killed,” Swank wrote on March 14, adding that a Reuters report had exaggerated the damage.

On the day of the shooting, Swank wrote that there was considerable chance that the government’s policy would be successful “for the moment at least, in cooling the situation”.

But by March 20, the two grenade victims were being laid to rest at a funeral service that the Khmer Student Association was not allowed to attend – and their killers remained free.