Siem Reap, Cambodia ? Masked gunmen burst into an international school near Cambodia’s famed Angkor Wat temples Thursday, taking dozens of toddlers hostage and killing a 3-year-old Canadian boy they said cried too much. Police overpowered the attackers as they tried to escape after a six-hour standoff.

Furious and sometimes weeping parents waiting outside the school took their revenge, bloodying three of the four hostage-takers and beating at least one unconscious before police pulled them away.

The attackers, motivated by a desire for money, barged into the school at about 9:30 a.m. and herded a teacher and almost 30 nursery school-aged children into a classroom in one of the school’s two buildings.

Scores of other children – from as many as 15 countries including the United States – managed to hide or scramble from the grounds. It was not known if any American children were held hostage. A U.S. Embassy spokesman in the Cambodian capital declined comment.

Parents rushed to the school and waited with soldiers and police, many sitting on the ground in any shade they could find against the heat of the day as authorities negotiated with the attackers.

As the hours stretched on, the occasional sound of captive children crying could be heard from inside the school grounds beyond a small empty playground.

Children are rushed from the grounds of the Siem Reap International School in Siem Reap, Cambodia, during a hostage standoff Thursday. At least one child was killed when masked gunmen stormed the school demanding money and weapons

The attackers demanded money, weapons and a vehicle, and Cambodian officials partially complied, delivering $30,000 and a van.

The attackers got in the van along with four children, but as they prepared to drive off, security forces closed the school gate and stormed the vehicle, dragging the men out, military police officer Prak Chanthoeun said.

Some parents charged the hostage takers.

“Those parents beat and kicked those men because they were very outraged by them. We could barely control the angry crowd,” he said. “One foreigner threw several hard kicks to the head of one of those men.”

Other parents were seen grabbing their children and dashing away from the school yard.

The gang’s leader, identified as Khum, later told police he had shot the Canadian toddler in the head, Chanthoeun said. “This man admitted he shot the child because the child was crying a lot,” he said.

Other officials said earlier the boy was shot because officials did not fulfill all the hostage takers’ demands, and that they had threatened to shoot others. After they were taken into custody, police discovered they only had one gun among them, Chanthoeun said.

The hostage-takers came from a district near the capital, Phnom Penh, to work in Siem Reap. They told police they were penniless and “decided to do that to the foreign children because they believed their families are rich,” said Chanthoeun, who described them as small town gangsters.

Cambodia is one of the poorest countries in the world, and the government hopes tourism can help improve the desperate conditions.

Tan Seok Ho, 42, a Singaporean woman who runs a language school in the town and is the mother of a three-year-old taken hostage, said her son did not appear traumatized afterward and he said only that the school was “broken.”

“I think it was his childish way of saying there was damage done to his school,” she said.