Turkey’s invasion of northeastern Syria has begun, days after the Trump administration relocated US troops stationed in the region.

Turkish President Recep Tayyip Erdogan announced Wednesday that the Turkish military and Turkish-backed Free Syrian Army had launched an offensive into northeastern Syria, bombing and shelling territory that’s under the control of the US-backed Syrian Kurdish fighters and putting the lives of thousands of civilians at risk.

A press officer for the Syrian Democratic Forces (SDF), which is led by Kurdish fighters, said that Turkish planes have begun to carry out airstrikes on civilian areas. “There is a huge panic among people of the region,” Mustafa Bali, the press officer, wrote.

Turkish media showed bombings of border towns, and reports say that Kurds were fleeing some border towns, including Ras al Ain and Tel Abyad. The Syrian Democratic Forces said that at least two civilians had been killed in the “Turkish aerial bombardment” in the village of Mosharrafa, west of Ras al Ain.

The Turkish military initiated a ground offensive across the border into Syria late Wednesday, according to the Washington Post.

The Turkish incursion across Syria’s border was imminent after the White House said earlier this week that it was relocating troops from the area in anticipation of Turkey’s advance.

Though the Pentagon and White House officials later tried to clarify that the US did not support or endorse Turkey’s impending offensive, both Democratic and Republican lawmakers and former officials condemned President Trump’s decision to move troops and accused the administration of abandoning the Kurds — the US’s key partner on the ground in Syria in the fight against ISIS — and leaving them exposed to slaughter.

“The Turkish Armed Forces, together with the Syrian National Army, just launched #OperationPeaceSpring against PKK/YPG and Daesh terrorists in northern Syria,” President Erdogan wrote on Twitter. “Our mission is to prevent the creation of a terror corridor across our southern border, and to bring peace to the area.”

“#OperationPeaceSpring will neutralize terror threats against Turkey and lead to the establishment of a safe zone, facilitating the return of Syrian refugees to their homes,” Erdogan continued. “We will preserve Syria’s territorial integrity and liberate local communities from terrorists.”

Erdogan’s statement is disingenuous on many fronts, the most obvious being that Turkey’s encroachment into Syria is likely to create even more chaos and bloodshed, rather than the peace or protection from terrorism that Erdogan is promising.

Turkey wants to establish a “safe zone” within Syrian territory to push back on Kurds near the Turkish border, who have de facto control over the northeastern region of Syria. In this zone, Erdogan also wants to resettle many of the approximately 3.6 million Syrian refugees who’ve fled to Turkey in the years-long civil war.

The Syrian Democratic Forces (SDF), who are led by Kurdish forces, helped defeated ISIS’s territorial caliphate, leading the battle against the jihadists in places such as Raqqa.

But Turkey sees the Kurds’ presence close to its border as an existential threat, as they’re linked to the Kurdistan Workers’ Party (PKK), a separatist group that’s waged an insurgency in Turkey for decades. Both Turkey and the US classify the PKK as a terrorist group, and Erdogan has become agitated as the Syrian Kurds have established control over the region right across the border.

The US had been working with Turkey since August to try to ease Erdogan’s security concerns, conducting joint patrols and incrementally establishing a buffer zone across the border, by pushing back and destroying some Syrian Kurdish fortifications.

The Pentagon touted this strategy as recently as last week, right before Trump’s abrupt announcement that US troops were getting out and Turkey was coming into northeastern Syria. The Kurds, meanwhile, argued that they cooperated in this initiative, and now they’ve been left “defenseless.”

“This attack will spill the blood of thousands of innocent civilians because our border areas are overcrowded,” the SDF said.

Turkey also wants to use this “safe zone” as a staging ground for returning refugees to “resettle them in their homeland.” Erdogan is under a lot of pressure in this regard, as backlash against Syrian refugees is growing in the country.

Of course, the millions of Syrian refugees who fled are from different parts of the country, and many of the displaced are Syrian Arabs, who — according to Erdogan’s desires — will now be resettled in a Kurdish area, displacing the native population and potentially inflaming ethnic tensions. The United Nations has warned that a protracted Turkish offensive against Syrian Kurds could create another refugee crisis, rather than help solve the existing one.

The SDF has called on the international community to condemn the attack, and has asked the United States and its coalition partners in Syria to establish a no-fly zone to protect its people.

Republican and Democratic lawmakers are continuing to speak out against Trump’s decision to abandon Kurdish allies and are warning about the potential fallout — including the risk of ISIS returning — from this move.

Other US allies have been slightly more forceful in speaking out against Turkey, a fellow NATO ally. The United Kingdom and France are planning to call for an emergency United Nations Security Council meeting about Turkey’s invasion. The European Commission president, Jean-Claude Juncker, warned Turkey to “act with restraint,” and said it would take no part in Turkey’s establishment of a “safe zone” for refugees. (The EU gives financial support to Turkey for its refugees, an effort to stem the continent’s own migration crisis.)

NATO Secretary-General Jens Stoltenberg acknowledged that Turkey, a NATO ally, had legitimate security concerns, but that the country must avoid any actions that “destabilize the country further.”

German officials also warned that Turkey risked a humanitarian disaster, and that invasion could spark the resurgence of ISIS.

ISIS fighters were routed in the past few years, resulting in the loss of the organization’s territorial caliphate, and the Kurdish forces in Syria were a huge reason why. But experts — including the Pentagon — have worried for months that ISIS could reconstitute, and still threaten the US and its allies with terror attacks.

And Turkey’s attack is likely to make the situation even more untenable. On Wednesday, the SDF reportedly stopped all operations to defeat ISIS, and the SDF said that Turkey had attacked a camp, where Kurdish fighters had previously trained to battle ISIS.

Syrian Democratic Forces are also the guardians of thousands of ISIS prisoners, including overseeing the al-Hol refugee camp filled with tens of thousands of ISIS families that’s widely known to be a recruiting ground for the terror group. The SDF capacity was stretched to begin with, but analysts and experts fear that if Kurdish troops are pulled away to fight off Turkey or protect civilians, then these ISIS fighters could attempt a mass prison break and exploit the chaos that a Turkish invasion would bring.

Trump said in a statement Wednesday that Turkey is responsible “for ensuring all ISIS fighters being held captive remain in prison and that ISIS does not reconstitute in any way, shape, or form.” But how the US can even hold Turkey to that commitment is totally unclear.

Kurdish officials, of course, have an incentive to show the fallout of Turkey’s invasion — but the grave humanitarian risk and the opportunity for ISIS were predicted long before Turkish warplanes began their assault.

Turkey is sending troops and tanks to its border with Syria hours after President Trump announced he would be removing US forces from the nation. Syrian Kurds feel betrayed and ISIS is watching.

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