Ahmed Taufik fled his hometown of Tal Abyad once before, when Isis fighters stormed the streets where he grew up and eventually took control in 2014. Today, he is contemplating having to do it all over again.

Residents in this small border town are bracing for a long-threatened Turkish offensive against the Kurdish forces that control the area, following days of shelling and cross-border fire that has killed and injured civilians.

“The situation in the past few days has been very bad, a mortar landed not far from my house. If it stays like this, then we’re afraid Turkey will come,” said Mr Taufik, 42.

“I have two cars ready to go at all times in case we have to run,” he added.

The Turkish army has launched a wave of attacks over the Syrian border over the past week, ahead of what the country’s president Recep Tayyip Erdogan said was an imminent offensive to “destroy the terrorist establishment on the east of the Euphrates”.

The Kurdish-led Syrian Democratic Forces (SDF), to which Mr Erdogan refers, have been a key ally of the United States in the fight against Isis, and control a swathe of northern Syria. But Turkey views it as a terrorist group and has vowed to remove it from the border.

Following the attacks, which reportedly killed a 10-year-old girl and wounded two journalists, residents in the majority Arab town of Tal Abyad told The Independent they fear Turkey will make good on its many promises to move its forces east of the Euphrates River into Kurdish-held areas.

The attacks have brought to a head a long-simmering row between Turkey and the US over Washington’s support for the SDF, and threatened to derail the fight against Isis in Syria. In response to the shelling, the SDF postponed its offensive against the last few towns under Isis control in the country.

US soldiers visited some SDF positions in what a coalition spokesman called a “courtesy military visit in the area” on Friday, but SDF fighters in Tal Abyad said US presence had made little difference.“The Americans came for 30 minutes yesterday to check the situation and left, then the Turkish army started shooting again,” said one fighter, who declined to give his name.

Another fighter, Ali Halim Mirzo, said there had been a build-up of Turkish forces on the other side of the border over the past week.

“In the past there were only a few soldiers, now there are tanks and snipers all the way along,” he said.

On Friday, residents were steering clear of a normally busy road that runs along the border. Earlier that morning, two journalists working for a local news agency were shot by the Turkish army. One of them, 19-year-old Gulistan Muhammed, is in a critical condition. Her colleague, Ibrahim Ahmed, said from a hospital bed that they had gone to report on the shelling.

The shelling makes life very uncomfortable for the US and SDF and forces debates in Washington about how to manage and handle Turkey Aaron Stein, senior fellow at the Atlantic Council

The flare-up between Turkey and the SDF comes at a difficult time for the US-led coalition. The SDF, backed by US forces and airstrikes, has been battling to capture the last remaining piece of populated territory controlled by Isis in Syria – a string of villages in Deir Ez-Zour near the town of Hajin. But in the past week, Isis has managed to recapture nearly all the territory the SDF had taken.

The Turkish shelling began in the aftermath of the Isis counterattack, and led to the SDF announcing that it was halting the offensive.

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Mr Erdogan has repeatedly expressed his frustration over US support for the SDF, which is primarily made up of fighters from the People’s Protection Units (YPG), an affiliate of a Kurdish group that has fought the Turkish state for decades.

"Aren't you strategic partners with us? We asked to purchase weapons from you and you rejected, but you give this terrorist group weapons for free. How do you explain this to the world?” Mr Erdogan said last month, referring to US backing of the group.

Aaron Stein, a senior fellow at the Atlantic Council, said Turkey’s strategy is “to put pressure on the United States to acquiesce to Ankara's long standing demand to force the YPG from the border areas and to replace Kurdish-linked councils with groups in Ankara's orbit.”

“The shelling makes life very uncomfortable for the US and SDF and forces debates in Washington about how to manage and handle Turkey,” he added.

Over the past two years, Turkish forces have launched two separate offensives to push YPG fighters out of territory in northern Syria, but they have so far stopped at the Euphrates River due to the presence of US forces on the other side.

Deputy State Department spokesman Robert Palladino made a point of reminding Turkey of that on Thursday, saying that “unilateral military strikes into northwest Syria by any party, particularly as American personnel may be present or in the vicinity, are of great concern to us.”