Turkey's security forces detained nearly 500 people attempting to cross the border from war-torn Syria on Saturday, the army announced.
"488 people were detained by the land forces command border units while trying to cross into Turkey from Syria and 26 while attempting to cross into Syria from Turkey," the army said on Sunday in a statement posted on its website.
The army statement did not reveal the nationalities of those detained.
Turkey has often boasted of an "open-door" policy championed by President Recep Tayyip Erdogan and taken in 1.8 million refugees since the Syrian conflict started in 2011 but has repeatedly complained that it has been left to shoulder an unfair burden.
Several hundred thousand refugees are sheltered in camps along the border with Syria but the vast majority of them are scattered throughout the country including the mega city Istanbul.
Turkey has long been under international pressure to tighten the security of its volatile 911-kilometre border with Syria to cut the flow of jihadists who try to join the ranks of ISIS militants who have made gains in Iraq and Syria.
Turkish authorities have fiercely rejected the accusations, saying it is making every effort to secure a long border but no tangible results can be obtained unless Western states share more intelligence about would-be jihadists.
In an apparent bid to deflect criticism, Turkish authorities have arrested over the last week dozens of suspected IS militants.
Turkey has also beefed up its military presence on the border in recent weeks, deploying tanks and anti-aircraft missiles there as well as additional troops.
The Turkish build-up follows the advance of Syrian Kurdish forces who have made gains against the extremists in northern Syria near the border.
Cross-border smuggling is also common on the Turkish-Syria border, and tobacco is one of the most frequently smuggled illicit goods. The army also said 97 packs of cigarettes and 32,4 kilograms of hashish were seized on Saturday.SHOW MORE