"While the four robbers have confessed to their crime, the hunt is on for the rest. Rs 3,550 cash and a knife were seized from the possession of each robber," SP Railway G N Khanna said.
The robbers have confessed that they looted the passengers, including Malaiya and his wife, travelling in the AC1 coach of Jabalpur-Nizamuddin express.
On a tip-off, the robbers were arrested from Mathura junction, he said.
Gold chain, ring and some cash were looted from the minister and his wife at dagger point in the AC compartment of the running train on March 19. The couple had boarded the train at Damoh for Delhi.
