GENEVA â€"  The U.N. human rights office says the global body's investigators have concluded that children were among almost 90 people summarily executed in the Syrian area of Houla on Friday.

A spokesman for the U.N. High Commissioner for Human Rights says U.N. monitors found that less than 20 of the 108 people killed died from artillery fire.

Rupert Colville told reporters in Geneva that most of the other victims were summarily executed in two separate incidents.

Colville says the conclusions of the U.N. monitors are corroborated by other sources.

He says witnesses blamed pro-government militias for the attacks.

The killings in the west-central area of Houla brought widespread international criticism of the regime of President Bashar Assad