BAGHDAD -- The U.N. Security Council is expressing alarm at reports that Islamic State extremists are removing civilians from their homes and relocating them to act as human shields in Mosul.

The council condemned the use of human shields and urged all parties to avoid harming civilians and civilian facilities.

Council members said in a statement Wednesday after their first briefing on the Iraqi military campaign to liberate Mosul from Islamic State control that they don’t want to see ISIS fighters fleeing across the border to Syria.

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The council statement, however, made no mention of support for the Iraqi military effort, which Iraq’s U.N. Ambassador Mohamed Alhakim had sought. Senegal, which holds the council presidency this month, said that issue is still under discussion.

Council members did express “strong support” for the coordinated efforts of the United Nations and the Iraqi government to address the humanitarian crisis. They urged all countries to contribute to the underfunded U.N. appeal to help those displaced as the military operation continues.

The Iraqi military--backed by U.S. airstrikes and other special forces--on Tuesday pushed into the city limits of Mosul, Iraq’s second-largest city, as part of the offensive that began in October. It was the first time Iraqi troops have set foot in the city in more than two years, and the fight is expected to last months, not weeks.

A spokesman for a leading Shiite militia, who have joined in the fight against ISIS, says its fighters have gained control of a highway linking the ISIS-held city of Mosul to the Syrian city of Raqqa, the de facto capital of the militants’ self-proclaimed caliphate.

The spokesman for the Hezbollah Brigades, Jaafar al-Husseini, said Wednesday that his troops are now cutting the main supply line to the militants.