The United Nations says more than 54,000 people have been displaced in Mosul, where a massive Iraqi military operation is underway to free the city from Islamic State militants.
A U.N. spokesman, Farhan Haq, said Monday the number of displaced people has increased by 6,600 since Friday, with most of them fleeing to displaced persons camps.
Iraqi special forces say they are checking all displaced people for suspected links to Islamic State before allowing them into the camps. They say they have also cleared the Qadisiya and Zahra neighborhoods in Mosul.
The Iraqi troops, backed by a U.S.-led coalition of airstrikes, are moving slowly through the city, trying to avoid casualties to armed forces and civilians as IS militants detonate suicide bombs.
U.S. Secretary of Defense Ash Carter said in a discussion Monday in Washington with The Atlantic magazine and 1776, a global business incubator, that the Iraqi cities of Mosul and Raqqa are the "two central nodes" of Islamic State.
"They have to be destroyed. Our plan early on involved the systematic envelopment of those two forces of those two cities and the destruction of ISIL within them,” he said, using an acronym for Islamic State. “For a year now, we have been planning that and working with Iraqi forces and the peshmerga."
WATCH: Carter Talks about Fight in Mosul, Raqqa
The World Food Program says it has provided food assistance to more than 100,000 people in Mosul and the surrounding areas. It said that includes a distribution on Sunday to 25,000 people in Gogjali, the first neighborhood inside Mosul retaken by Iraqi's army.
The U.N. agency said it is providing family food rations that include rice, wheat flour, chickpeas, vegetable oil, sugar and salt to people in both camps and neighborhoods.
"WFP is concerned about the food security of people trapped inside Mosul, and in areas surrounding the city,” said Sally Haydock, WFP Country Director in Iraq. “Together with our partners, we are monitoring frontlines and working to reach families in need as soon as there is safe access."