MUMBAI: Chetan Singh, the RPF constable arrested for gunning down four people on the Jaipur-Mumbai Superfast Express on Monday, had spoken to his wife over the phone after the crime and told her she had to raise the kids on her own now, police investigations have shown.On Saturday, Singh’s wife, Renu, and mother came down to Mumbai from Mathura and recorded their statements before Borivali GRP. Read AlsoKiller RPF cop Chetan Singh cited scrotum pain on train, senior dismissed it as excuseChetan Singh, the RPF escort held for...