CNN  — 

Turkey has launched a military operation in Syria. Here’s what you need to know.

What happened Wednesday?

Turkey launched a military offensive into northeastern Syria on Wednesday, just days after President Donald Trump’s administration announced that US troops would leave the border area.

As a barrage of airstrikes and artillery fire volleyed into northern Syria, hundreds of civilians fled areas on the border with Turkey, two Kurdish People’s Protection Units (YPG) fighters and witnesses told CNN.

Tal Abyad in northern Syria and the border town of Ras al-Ain were among the areas that were targeted, a US official familiar with operations in the region said.

Why is Turkey attacking?

“Our aim is to destroy the terror corridor which is trying to be established on our southern border and to bring peace and peace to the region,” Turkish President Recep Tayyip Erdogan tweeted, announcing that the operation had begun.

The Syrian Democratic Forces (SDF) who operate in the region are Kurdish-led. And while the Kurds have been Washington’s staunchest and most effective allies in the war against ISIS, Turkey regards the YPG as a terrorist group affiliated with the Kurdistan Workers’ Party (PKK) – which has fought the Turkish state for more than three decades.

The Turks have long been extremely unhappy about the strong Kurdish presence in northeast Syria near the Turkish border. Turkey’s military had already moved into portions of areas previously held by SDF, but now Washington’s decision provided Ankara with the green light to follow through on its plans to create a buffer zone in northern Syria.

Turkish President Recep Tayyip Erdogan.

Turkey does not only want to ensure that the Kurdish forces withdraw from these areas, they also want to resettle around 2 million Syrian refugees there. During the worst of the fighting of the Syrian conflict, around 3.6 million Syrians fled to Turkey. Many of those people are now either living in giant makeshift camps or in towns in the border region. The Turks hope to achieve two objectives by creating a buffer zone: drive the Kurds away from their border and repatriate a large number of Syrians.

What’s been happening in Syria lately?

Syria’s devastating, years-long war recently moved into a new phase which could be described as one of “consolidation.”

With the help of Russia and Iran, the Syrian military managed to all but defeat the insurgency looking to unseat Syrian President Bashar al-Assad.

At the same time, the US-led coalition with the SDF – and to an extent Russian and Iranian forces – drove ISIS to the brink of destruction, at least territorially.

ISIS holds virtually no more territory. However, the US warns there are still tens of thousands of ISIS fighters hiding in both Iraq and Syria.

The SDF still holds thousands of ISIS fighters captured in battle. Many of those fighters are from foreign countries, often from Europe.

The Trump administration has long warned European nations that the US will have to release them, if the Europeans don’t take their citizens back.

Now, Trump says Turkey could take responsibility for the captured fighters. No plan for a prisoner handover has been made public.

How did the SDF react?