Three Palestinian refugees were severely burned and 25 others, mostly children, were treated for minor burns and smoke inhalation when a fire broke out in tents along the Syrian-Iraqi border, the UN refugee agency said Wednesday. Investigators have not determined what started the blaze Tuesday night at the Tanaf checkpoint, 306 kilometers (190 miles) northeast of Damascus, but a resident there told The Associated Press by telephone it was caused when an electric circuit caught fire. The United Nations High Commissioner for Refugees said in a statement the fire spread rapidly to other tents because of strong winds. Seven tents were destroyed. Of the three people who were severely burned, none of the the injuries appeared life threatening. There are 389 people living in tents at a makeshift refugee camp on the Tanaf border crossing with Iraq, most of them women and children.