Police have stepped up security at prominent railway stations in the city after an anonymous caller threatened to blow up "Bombay" railway station, an official said today. The control room of the Railway Protection Force (RPF) received the call around 1.10 pm today, in which the caller threatened the duty officer about the possible blast at a\u00a0railway station, the official said. The RPF official immediately sent an alert to all the agencies and also informed the Government Railway Police (GRP), he said. "As the caller mentioned 'Bombay' station, the Bomb Detection and Disposal Squad (BDDS) and a dog squad were rushed to the Bombay Central Railway Station to avoid any\u00a0untoward incident there," he said. Tight security arrangements have been put in place at other prominent railway stations like Churchgate, Chhatrapati Shivaji Maharaj Terminus (CSMT) and Dadar, among others, an\u00a0official said. "After getting the information, we sent an alert to all the railway stations and also increased the police presence there," Deputy Commissioner of Police (GRP) Samadhan Pawar said. "We carried out searches at these railway stations, but did not find anything suspicious. Though there was nothing specific, we are on toes and trying to find out from where the\u00a0call was made," he said.