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.
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Robert Gropel asked his wife to wait while he hiked to the peak, not realising she had altitude sickness that would prove fatal.
Severe weather warnings have been issued as up to 60mm of rain is set to fall within just a few hours in some parts.
Tuesday: A cloudy, cool and dull day with outbreaks of heavy rain becoming lighter and patchier.