T Sukuraman, a Canadian citizen, took the metro from Karol Bagh and deboarded at Rajiv Chowk on May 8, they said.
While alighting he found that a black purse containing USD 8,300, his passport and other documents was missing, they added.
He filed a police complaint and police scanned the CCTV footage from the cameras.
Within 24 hours, they arrested six women from Ghazipur for their alleged involvement in the theft.