A Railway Protection Force (RPF) personnel on Monday morning shot dead four people, including an Assistant Sub-Inspector, on-board a running train near the Palghar railway station in Maharashtra, an official said. He was later arrested after attempting to run away. "Four casualties, including the ASI, have been reported in the firing incident inside the Jaipur-Mumbai Central Superfast Express (12956). The accused has been arrested. DCP North GRP has been informed," the Railway Protection Force has said.