The CIID sent a letter to the WB country director on Wednesday, asking for details of those vehicles, CIID Director General Moinul Khan confirmed the Dhaka Tribune.
The cars were used by high- and mid-level officials of WB’s Dhaka office.
According to Moinul, duty-free vehicles can be imported under the Privileged Persons (Customs Procedure) Rules 2003.
Officials of specified international organisations, UN bodies or development partners are defined as privileged persons according to the rules.
The National Board of Revenue issues customs passbook against a car imported duty-free for officials of these organisations recommended by the mission heads concerned.
The person availing the benefit has to hand over the passbook and submit car details to the customs during their departure from Bangladesh.
Most of the WB officials had left the country without handing over the passbook, said Moinul.