Heavy machine gun fire and the sound of mortar bombs has been heard along the Turkey-Syrian border near the Syrian town of Haram, according to a Reuters witness.
It was not clear whether the firing was from the Syrian army or from rebels fighting to overthrow President Bashar al-Assad.
The firing could be heard from the Turkish border village of Besaslan in southern Hatay province.
More top news
Edinburgh and its institutions have been at heart of the Union since it came about in 1707, here we look at the city's history.
In Berwick-upon-Tweed - the town at the northern-most tip of England - history has taught them that no border necessarily lasts forever.
His car was about to get towed away. But he had other ideas.