Turkey ramped up its air and artillery strikes against the Kurds in northeast Syria Friday — forcing 100,000 people to flee the battle, as the White House threatened Turkey with harsh sanctions.

The Kurds, who recaptured swaths of northeastern Syria from ISIS as US allies, said the Turkish assault could allow the jihadist group to re-merge.

That warning was highlighted Friday as the terror group claimed responsibility for a deadly car bomb in Qamishli, the biggest city in the Kurdish-held area, even as the city came under heavy ­Turkish shelling.

Five ISIS fighters fled a jail there, and foreign women from the group being held in a camp torched tents and attacked guards with sticks and stones, the Kurds said.

The Turkish invasion, launched after President Trump abruptly withdrew US troops who had been fighting alongside Kurdish forces against ISIS, has opened a new front in the eight-year Syrian civil war and drawn international criticism.

On Friday, Turkish warplanes and artillery struck around Syria’s Ras al-Ayn, one of two border towns that have been the focus of the offensive, now in its third day.

A war monitor gave a death toll approaching 100 from the first days of the assault, and the UN said 100,000 people had fled their homes.

Meanwhile, some US special forces troops were caught up in the middle of the action when Turkey shelled Kurdish positions in northern Syria — days after Trump told his Turkish counterpart he would withdraw US troops from the area, Newsweek reported Friday.

A senior Pentagon official said that shelling by the Turkish forces was so heavy that the US personnel considered firing back in self-defense but ultimately withheld their fire and withdrew without injuries when the shelling stopped.

Fending off accusations he had abandoned the Kurds, Trump suggested Washington could mediate in the conflict.

He also raised the possibility of imposing sanctions on Turkey — a move demanded by Republican congressional critics of the pullout.

Treasury Secretary Steve Mnuchin said Friday that the administration was not slapping sanctions on Turkey at this time — but that Trump would be giving his department “significant new sanctions authorities” to target “any person associated with the government of Turkey” in the future.

The penalties were being readied so that Trump could follow through on his threat to “obliterate” the country’s economy if circumstances deteriorate.

“I want to emphasize at this point, we are not activating the sanction,” Mnuchin told reporters at a White House briefing.

“The president is concerned about the ongoing military offensive and potential targeting of civilians, civilian infrastructure, ethnic or religious minorities and also the president wants to make very clear it is imperative that Turkey not allow even a single ISIS fighter to escape,” he said.

With Post wires