A number of Bangladesh nationals have left for Afghanistan to join the Taliban, Dhaka Metropolitan Police (DMP) Commissioner Md Shafiqul Islam said, adding that some are trying to reach there on foot as well.

"Recently, the Taliban has urged people to join the war in Afghanistan and some people, responding to their call, have left home," the DMP chief said.

"It is our guess that some people from Bangladesh have been caught in India, and some are trying to reach Afghanistan on foot in various ways," he added.

He said that the hardline Islamist group has been using social media to recruit people for their war in Afghanistan.

Some of them were caught from the Indian border, he added.

Intelligence agencies in Bangladesh remain vigilant and vulnerable areas have been placed under CCTV surveillance.