More than 5,000 people demonstrated in the eastern Afghan city of Jalalabad Thursday to protest the deaths of four children and wounding of scores of others in an explosion that ripped through a crowd in a nearby village the day before.

The crowd blockaded the main highway to the Pakistan border for hours, shouting “Death to America” and burning US President Barack Obama in effigy.

Despite NATO denials of responsibility for the carnage and a claim by local police that the blast was caused by a police vehicle hitting a landmine, Afghans blamed the deaths on the US-led occupation.

The incident took place Wednesday as a group of US soldiers were visiting a road-construction site in the village of Mazzina. The village lies south of Jalalabad, which is the capital of Nangarhar Province.

Witnesses reported that the soldiers had begun throwing candy to local children when the blast took place.

The New York Times quoted a 38-year-old Afghan, Naimtullah, who said he had witnessed the incident: “I saw them throwing chocolate to the students and then suddenly they threw a grenade, followed by shooting.”

The Times also quoted the uncle of one of the boys killed in the explosion, Salim, who denounced the occupation forces. “These people are here to help and protect us, or they are here to kill us—we don’t want them anymore.”

US military spokesmen and representatives of the security forces of the Afghan puppet regime pointed out that several American soldiers had also been wounded by the blast.

While the precise cause of the explosion may be in dispute, the significance of this sudden, violent transformation of what was intended as a “hearts and minds” mission to win over the local population into a provocation igniting mass anti-US protests is clear.

It is a telling expression of the mounting popular hostility to foreign occupation and the growing crisis confronting the US military as the Obama administration embarks on its 30,000-troop escalation of the eight-year-old war.

The killing of the four children Wednesday was far from an isolated incident. Afghan children are dying at the rate of at least three a day as a result of the US war and account for the majority of its civilian victims, according to a report released this week by an Afghan human rights group.

“At least three children were killed in war-related incidents every day in 2009, and many others suffered in diverse but mostly unreported ways,” said Ajmal Samadi, the director of the Afghanistan Rights Monitor (ARM) in the report.

According to the figures compiled by ARM, more than 1,050 children under the age of 18 were killed in war-related violence in 2009.

The report singled out the killing of eight students in eastern Kunar Province by US special operations forces on December 26 “an appalling act of crime against civilian people” by foreign forces and their Afghan supporters.

The massacre in Kunar also triggered mass protests against the US occupation.

While NATO initially insisted that all those killed in the raid were “insurgents,” subsequent investigation by both the United Nations and the US-backed regime of President Hamid Karzai found that eight of the victims were children, ages 11 through 17, all enrolled at local elementary and secondary schools. A ninth child, a 12-year-old shepherd boy, was also killed, along with a farmer.

The Times of London interviewed the local school principal, who described the killings. After landing in helicopters at one in the morning, the US commandoes assaulted a house where seven of the students were sleeping in one room, while the eighth student and the shepherd boy were in a guest room.

“First the foreign troops entered the guest room and shot two of them,” the school principal said. “Then they entered another room and handcuffed the seven students. Then they killed them. Abdul Khaliq [the farmer] heard shooting and came outside. When they saw him they shot him as well.”

Following the UN investigation, the international body’s special representative in Afghanistan, Kai Eide, condemned the US military’s night-time raids on Afghan homes.

“The United Nations remains concerned about night-time raids given that they often result in lethal outcomes for civilians, the dangerous confusion that frequently arises when a family compound is invaded, and the frustration of local authorities when operations are not co-ordinated with them,” he said. He added that the raids “are a source of great distress to the families which are directly affected as well as communities throughout Afghanistan given safety and cultural concerns.”

In a subsequent article from Kabul, the Times reported that the Afghan regime’s security council, chaired by Karzai, had demanded that the occupation forces “hand over” those responsible for the killings.

The newspaper also cited unnamed NATO sources as saying that “the foreigners involved were non-military, suggesting that they were part of a secret paramilitary unit based in the capital.”

The newspaper did not clarify the nature of this secret unit. The Central Intelligence Agency is carrying out its own “surge” in Afghanistan, and could potentially have mounted such a raid.

And, as the recent suicide bombing that killed seven CIA operatives made clear, the private security firm Xe—formerly known as Blackwater—remains active in Afghanistan. Two of the dead were Blackwater employees working as CIA contractors. Their presence has exposed as a lie the agency’s claim that it had terminated its contracts with the company.

Whether the execution-style slaying of handcuffed school children was carried out by the US military, the CIA or hired mercenaries, it constitutes an atrocity and a war crime for which the Obama administration bears political responsibility.

The pouring into Afghanistan of 30,000 more US troops—including a substantial increase in the number of special operations forces—will mean a steady increase in the number of such atrocities and the deaths of thousands, if not tens of thousands, more Afghan children.