"The UN Refugee Agency (UNHCR) is concerned about the shortage of shelter as the displacement numbers increase in Iraq," Xinhua quoted deputy UN spokesperson Farhan Haq as saying at a daily news briefing.
"Some 300,000 people are reported to have arrived in Erbil and Duhok with little more than the clothes they were wearing," Haq said. "Many families in Duhok are sheltering in schools, mosques, churches and unfinished buildings."
"A growing number of people were now staying in a transit camp near the Khazair checkpoint, near Mosul," he said. "UNHCR has helped the Iraqi government set-up tents and is providing other relief items."
Other UN agencies are installing latrines and water tanks, he said, adding that a new camp, expected to host some 3,000 people, has been set up near Duhok in the Kurdistan region.
"Two more sites are being planned in the area," he said.
"UNHCR has observed that some Mosul families are returning after hearing that water and electricity services have been restored," he said. "As many as 25,000 people are displaced within Mosul."
Islamic insurgents seized Iraq's second largest city of Mosul, capital of the Nineveh province, Tuesday following days of fighting against government forces. As many as 500,000 people have reportedly fled Mosul in the wake of the violence. On Wednesday, terrorists kidnapped the consul general of Turkey and several consulate staff working in the city.
The World Health Organization (WHO) said that health clinics have been set up at displacement sites and health partners are working with the government to provide basic services including medicines and surveillance to families stranded at checkpoints.
WHO and the UN Children's Fund (UNICEF) will be providing measles vaccination for those entering into camps in the next few days, Haq said.
"UN agencies are moving further supplies into the country in anticipation of further displacement, including a World Food Programme-organised flight from Dubai is being planned to transport humanitarian supplies to Erbil," he said.