Turkish authorities have seized a large quantity of chemicals from a convoy trying to illegally enter the country from Syria, which "could be transformed into weapons".

Turkish authorities have seized a large quantity of chemicals from a convoy trying to illegally enter the country from Syria, which "could be transformed into weapons", the army said Sunday.

The convoy of three vehicles refused to stop as it attempted to illegally cross the border on Saturday near the southeastern town Turkish town of Reyhanli, the army said in a statement.

Para-military police were forced to shoot out the tyres of the vehicles to stop them, and three drivers jumped out and fled in the direction of Syria.

One of them was arrested, the army said without specifying his nationality.

The haul of sulphur and another unidentified substance will be examined by a team of army specialists, the statement said.

The Organization for the Prohibition of Chemical Weapons (OPCW) reported on Thursday that Syria's entire declared stock of chemical weapons has been placed under seal.

This included 1,000 tons of chemical agents, which can be used to make weapons, and 290 tons of chemical weapons.

A UN Security Council resolution stating that the arsenal must be destroyed by mid-2014, was agreed by the United States and Russia to avert military strikes on Syria after deadly chemical weapons attacks near Damascus in August.