Turkey is sending missile batteries and army vehicles to the border with Syria as a "security corridor", almost a week after the Syrian downing of a Turkish military jet, media reports said.
There was no official confirmation of the reported military moves.
About 30 military vehicles accompanied by a truck towing missile batteries left a base in the southeastern province of Hatay for the border, about 50 kilometres (30 miles) away, the Milliyet newspaper reported.
The Taraf newspaper, citing unnamed sources, said the deployments represented the establishment of a "de facto security corridor" on Turkish soil.
The moves follow the downing of a Turkish Phantom F-4 jet by Syrian fire over the eastern Mediterranean on Friday in what Prime Minister Recep Tayyip Erdogan said was a "heinous attack".
Turkey's powerful army has not confirmed the deployments, but earlier dismissed reports that it was "on alert" after the downing of the jet, whose two crew members are still missing.