“Four months ago, Turkish security forces found a two-kilogram cylinder with sarin gas after searching the homes of Syrian militants from the al-Qaeda and al-Nusra. They are using our borders to take the gas into Syria,” Mohamad Gunes said.

“The Syrian president has no reason to kill his own people,” he added.

People in the southern province, which borders Syria, said the weapons were used by the al-Qaeda-linked al-Nusra Front militants and not the Syrian government.