A U.S.-backed militia in Syria is warning the last remaining Islamic State fighters there to surrender or die.

Dozens of trucks appeared on the outskirts of the village of Baghouz on Tuesday to evacuate any Islamic State fighters who decide to give up, along with their families.

The Kurdish-led Syrian Democratic Forces said they will attack after evacuating civilians.

But U.N. human rights officials said they are concerned about the estimated 200 families holed up in Baghouz. They said IS fighters are actively preventing women and children from leaving.

Thousands of people, including civilians and some suspected foreign fighters who had joined IS, have streamed out of Baghouz in the past several weeks.

The Trump administration wants European countries to take back their fighters who fled home to join the militants.

Britain has refused and is stripping them of their citizenship. France has also shown little enthusiasm for repatriating ex-Islamic State fighters.

Kurdish forces who have been fighting IS with the support of U.S. forces said they expect total defeat of IS in Syria by the end of the week.

"In a few days, we will announce a great victory over the largest terrorist organization that waged war on the world," a senior Kurdish fighter said Tuesday.