A Delhi-based crew member of Jet Airways has been apprehended with US$480,200 (valued at Rs 3.21 crore) on board a Delhi-Hong Kong flight in a late-night raid on Sunday by the Directorate of Revenue Intelligence (DRI), officials from the agency said.

DRI officials said the initial investigation suggested the woman crew member was part of an elaborate scheme to bring back gold to the country in exchange for black money. The interrogation of the crew member has led the DRI to a travel company owner, who appears to be the mastermind of the scheme, the officials said.

"The travel company owner used to collect money from businessmen in Delhi and give it to the crew member. She used to hand over the money to someone in Hong Kong. The gang would then bring in gold illegally to convert the black money into white. At least 10 businessmen and some other airline crew members are on our radar," a DRI official, who asked not to be named, told Hindustan Times.

Investigators said that they had discovered that the crew member used to get one per cent of the total money smuggled and that she had been doing this for at least one month.

"She kept the money in foil paper, which the scanner at the airport was not able to detect easily," the official added.

A Jet Airways spokesperson confirmed the incident. "During an inspection by the DRI team on January 8, 2018, a large sum of foreign currency was recovered from an employee of the airline. The employee has been taken into custody. Based on the investigations and inputs from law enforcement agencies, the airline will take further action," the spokesperson wrote in a statement.