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
A man is facing jail for killing his toddler son by force-feeding until he "drowned in his food"
The quartet are to work on a 'ground-breaking' project with former Spice Girls manager Simon Fuller.
At least 17 people are dead after an airstrike outside a school in Syria, activists said.