The video filmed on the Istanbul subway shows two young men wearing ISIL T-shirts freely heading for their destination. report presstv.com

This comes as shops in several countries have been promoting ISIL clothes, toy equipment and gifts.

The footage has raised major concerns that those purchasing such clothes are somehow showing loyalty to the terrorist group.

Experts say the footage circulating online appears genuine and has been corroborated by other reports.

Quoting Turkish government officials and media reports, The New York Times reported on Monday that Turkey is one of the biggest sources of foreign fighters for the Takfiri group, which has captured large swathes of land in Iraq and Syria.

The newspaper cited the example of one former fighter who had been taken to Syria along with 10 of his friends and joined the ISIL after 15 days of training in the city of Raqqa.

This is not the first time that media expose links between the Turkish government and Takfiri militants.

German television station ARD has recently revealed that an office, run by ISIL-affiliated Turks, helps foreign militants cross the Turkish border to join the terrorist group’s militants in Iraq and Syria. The report said militants have been paid up to 400 euros to join the battles.

The German state TV station added that there are more than 2,000 militants joining ISIL who come from Europe, adding that they enter Istanbul as a tourist and then cross borders into Iraq and Syria.

The West and its regional allies, including Qatar, Saudi Arabia, and Turkey, are reportedly giving financial and military support to the militants.