Mr Kumar, a 1979-batch IPS officer of the Haryana cadre, retired in September 2017, after heading the National Investigation Agency, an anti-terror probe organization, for over four years.
According to an official order, Mr Kumar has been appointed vigilance commissioner in the Central Vigilance Commission for a term of four years or till he attains the age of 65.
The post was lying vacant since February.
The Commission comprises central vigilance commissioner and two vigilance commissioners.
At present, KV Chowdary is the central vigilance commissioner and TM Bhasin is the other vigilance commissioner.
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