The case was registered at the Ghantaghar police station, police said.
Four people, including a hostel owner and a manager, were booked on Friday for not informing the authorities about the stay of 11 foreigners at the facility in Udaipur, police said.
The hostel management did not inform the CID-CB's local unit about the stay of foreigners which should have been done as per the rules, SP, CID-CB, Rajendra Prasad Goyal said.
The case was registered at the Ghantaghar police station, he added.
The foreigners, including citizens of the UK, the USA and Ireland, stayed at the hostel between 24th February and 20th March on different dates.
The matter is being probed, SP Goyal said