Two Chinese nationals were intercepted by CISF personnel at the Bagdogra airport on Tuesday for not possessing appropriate documents required to travel in a foreign country, just before they were about to board a flight to Hyderabad.

The Central Industrial Security Force (CISF) personnel, who man the airport, later handed over the duo to Bagdogra police. Different agencies of Siliguri Metropolitan Police have started interrogating the Chinese nationals and are trying are to find out the purpose of their travel.

According to police sources, the duo have been identified as Kailang and Zhang Jun. They had entered India via Panitanki, the transit point that is located on the India-Nepal border and around 35km from here.

During preliminary investigation, the police have come to know that they had been to Karachi in Pakistan from Nepal earlier this month.

“Both the Chinese nationals went to Karachi from Nepal on March 3. After spending a few days at the port city of Pakistan, they returned to Nepal. Then, they crossed the border and reached Bagdogra with a plan to take a Hyderabad-bound flight from here,” said an officer of Siliguri Metropolitan Police.

At the airport, the on-duty CISF personnel found that the documents which they were carrying were inappropriate.

“The CISF detained both and informed us. Later, they handed over the Chinese nationals to us. We have detained them and our officers are trying to collect more details from them,” the police officer said.

Sources said while one of them was carrying a Chinese passport but lacked a visa, the other did not have a passport at all.

“Interestingly, both of them were carrying Aadhaar cards which appeared to be fake. We have engaged our men to verify the documents. Altogether, their travel with Aadhaar cards and without visas has raised our doubts,” a senior police officer said.

A retired army officer pointed out that the police, central and state armed forces and different intelligence agencies always remained alert in north Bengal, particularly in Siliguri, considering the geographical location.

“This is because the area is known as Chicken’s Neck, where the width of the Indian sub-continent is narrow with Nepal and China on the north side and Bangladesh on the south side. It is one of the strategically important areas of India, particularly after the recent stand-off between Indian and Chinese troops. Those who have been detained should be properly interrogated to find out why they were here. They do not appear to be tourists as they lacked proper travel documents,” he said.