On Monday alone, an estimated 5,300 people crossed the main border crossing at Blace, said Kris Janowski, a spokesman for the Geneva-based UN High Commission for Refugees (UNHCR). UNHCR workers monitoring the border 24 hours a day said the flow was continuing today. While those moving over the weekend came primarily from the village of Aracinovo, outside of Skopje, the people who arrived on Monday came mostly from Skopje itself and its outskirts.According to UNHCR, the refugees cited growing tension between the country’s ethnic groups and the threat of a military confrontation outside Skopje as the main reasons for leaving. Most of those arriving were women and children, since men were being turned back at the official border crossing.Nearly 18,000 people had crossed into Kosovo since Friday, Mr. Janowski said. After receiving food and water at the border, most were being accommodated with host families.