Turkish special forces units supported by warplanes from the U.S.-led coalition launched an operation in northern Syria to wipe out Islamic State militants along the Turkey-Syria border, a Turkish government press office said on Wednesday.
The Turkish army began firing artillery rounds into the Syrian border town of Jarablus at around 0100 GMT, state-run Anadolu agency said.
White and grey plumes of smoke rose from atop hills in northern Syria, Turkey's CNN Turk television showed in footage broadcast live from the Turkish town of Karkamis across the border.
Turkey had vowed on Monday to "completely cleanse" Islamic State militants from its border region after a suicide bomber suspected of links to the group killed 54 people at a Kurdish wedding in southeastern city of Gaziantep.
The operation comes as Syrian rebels backed by Turkey had said they were in the final stages of preparing an assault from Turkish territory on Jarablus, aiming to preempt a potential attempt by Syrian Kurdish YPG militia to take it.
The Kurdish YPG militia, a critical part of the U.S.-backed campaign against Islamic State, took near complete control of Hasaka city on Tuesday. The group already controls swathes of northern Syria where Kurdish groups have established de facto autonomy since the start of the Syria war in 2011.
Their growing sway has been alarming Ankara, which is fighting its own insurgency with Kurdish PKK militants.
Turkey is focused on preventing the YPG or its allies building on recent advances against Islamic State by capturing the town of Jarablus. The U.S.-backed Syria Democratic Forces alliance (SDF), including the YPG, captured the city of Manbij, just south of Jarablus, from Islamic State earlier this month.