Harvinder Singh, Paramjit Singh and Satbir Singh from Haldaur in Uttar Pradesh were arrested while another accused identified as Satbir Singh from Ujjain in Madhya Pradesh is on the run, said G Koteshwar Rao, Government Railway Police (GRP) Inspector, Vizag.
The four had looted passengers on board several trains running between Hyderabad and here from September last year till this month, he said.
Harvinder used to survey the coach and zero-in on a few passengers whom the gang targeted when they were sleeping or had gone to washroom, the GRP inspector said.
After carrying out the loot, the three gang members used to get down at the next stoppage while Harvinder stayed inside the coach to avoid suspicion, he said.
Seven cases were registered against the accused and investigations are underway, police said.