The aftermath of the bombing in Syria's Afrin region on Saturday could be seen from the Turkish-Syrian border in Hatay province, Turkey © Reuters

Turkish fighter jets bombed a Kurdish enclave in north-west Syria on Saturday, defying calls from the US for restraint and injuring at least six people, two of them children.

The Turkish armed forces said an operation to force Kurdish militias from the Afrin region had officially begun after a week of threats by President Recep Tayyip Erdogan to attack.

Mr Erdogan said on Saturday that the assault would “destroy the terror corridor” along its border formed by members of the Kurdish YPG militia, which Turkey views as a big threat.

Ibrahim Ibrahim, a spokesman for the YPG’s political wing, said at least six people were injured in the air strikes, including two children, as two new fronts were opened in a region that has largely been spared from the worst fighting of Syria’s seven-year civil war.

Afrin, which has rarely been bombed, had been one of the few areas in north-western Syria left that was considered a haven for civilians fleeing fighting elsewhere.

“The Turkish warplanes are striking all areas [in Afrin], first and foremost civilian areas,” Mr Ibrahim said. “Most of Afrin is being hit with intense shelling.”

At least five jets were reported as being seen at the Turkish-Syrian border heading towards Afrin. There were also reports of a convoy of buses believed to be carrying Syrian opposition fighters to provide ground support.

The Syrian government denounced the attack and denied Turkish claims that they received a warning in advance.

Russia pulled out of Afrin before the attack, giving Turkey a de facto green light to move against Kurdish forces controlling the area. Moscow said the retreat of about 300 military police was a measure to ensure Russian soldiers’ safety.

“To prevent potential provocations, to exclude threats to the life and health of Russian servicemen, the operational group of the centre for reconciliation of warring parties and military police in the Afrin area was relocated to the Tell-Adjar area of the Tell-Rifat deconfliction zone,” the defence ministry said.

The Russian government did not criticise Turkey for the assault. The foreign ministry said it continued to search for solutions to the conflict in Syria based on safeguarding Syria’s territorial integrity and respecting its sovereignty. “In this regard, we call on the opposing sides to exercise mutual restraint,” the ministry said.

Moscow’s move followed two days of intense political and military consultations between Russia and Turkey. Moscow said Turkey had been pushed into its offensive by Washington’s moves to militarily support opposition forces in northern Syria.

“Ankara’s extremely negative reaction was prompted by Washington’s announcement that it was creating border forces in areas bordering Turkey,” the ministry said. “Such irresponsible US actions in Syria will derail the peace process and are hampering the intra-Syrian negotiations in Geneva in which the Kurds have a right to participate as well.”

The opening of new fronts in the Syrian civil war is likely to aggravate Turkey’s relations with the US, which backs Kurdish militia in Syria, and risks complicating a tangled situation on the ground.

Ankara considers the YPG an extension of the Kurdistan Workers’ party (PKK), which has waged a more than three-decade insurgency against Turkey. However, in northeastern Syria Washington has armed and trained a YPG-led force as its main partner in the fight against Isis in Syria.

Mr Erdogan reprised a longstanding threat to attack Afrin last weekend. His comments followed an announcement that the US-led coalition against Isis was planning to train a 30,000-strong border force in Syria’s north-east headed by the Kurdish-dominated Syrian Democratic Forces (SDF).

The YPG forces in Afrin are not part of the US-backed SDF. But Ankara deems all Syrian Kurdish forces in its border region as a threat.

Turkey has been amassing troops and tanks at the Syrian border since the start of the week. But the plan to invade Afrin was held up by Ankara’s need to consult Russia, a staunch backer of Bashar al-Assad, Syria’s president.

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