Turkish tanks crossed the border into Jarablus in northern Syria, state broadcaster TRT reported Wednesday citing military sources, while Syrian rebels forces told dpa they are also crossing into the Islamic State-held town from Turkey.
A number of Syrian rebel groups posted a message on Twitter saying the "storming operation, aimed at the first stage of liberating Jarablus," had begun. Among the groups, are Islamist factions and an ethnic Turkmen brigade.
Mahmoud al Ali, the head of the Jarablus Local Council, which ran the town before Islamic State invaded in 2013, told dpa: "A widescale military operation has started at dawn to liberate Jarablus and a number of the forces have crossed the border and are now inside the Syrian territories."
Turkey launched a number of airstrikes and cross-border shelling. The government says the operation is being conducted jointly with the US-led coalition against Islamic State. US Vice President Joe Biden is visiting Ankara.
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Syrian Kurds condemn the Turkish incursion into Islamic State-held Jarablus, calling it a "declaration of war."
The Syrian government says the Turkish operation in northern Syria is a "flagrant breach" of the country's sovereignty.
Turkish jets launched airstrikes against the northern Syrian town of Jarablus on Wednesday to clear it of Islamic State militants, state media reported saying it was a joint operation with the US-led coalition.