New Delhi: Vectra Chairman Ravi Rishi arrived at the CBI headquarters on Thursday for interrogations in connection with alleged irregularities in supply of Tatra all-terrain trucks to the Army.

Rishi has already been questioned by the CBI four times earlier. The 57-year-old British national Rishi is named as an accused in CBI's FIR in alleged irregularities in purchase of the Tatra trucks.

The CBI had registered a case naming Rishi and unnamed officials of Defence Ministry, Army and BEML on March 30 for alleged criminal conspiracy, cheating and relevant sections of Prevention of Corruption Act.

The CBI is probing alleged irregularities in assigning of supply from Czechoslovakia-based Tatra, with which the agreement was originally signed in 1986, to the Tatra-Sipox UK owned by Rishi in 1997 showing it as Original Equipment Manufacturer and the fully-owned subsidiary of Czech company

It is to be noted, a lookout notice was issued against Rishi on April 1 in the case.