A day after a woman was thrashed and paraded naked by a mob in Bihar's Bihiya town in Bhojpur district, the police arrested 15 suspects, but denied that it was a case of mob lynching.S.K. Singhal, Additional Director General (police headquarters), said 15 persons have been arrested on the basis of video footage of the incident."It was not a case of mob lynching at all. The police have been investigating it. None of the culprits would be spared," Singhal said.The ADG said the incident took place after the body of a youth was found on railway track in Bihiya town in Bhojpur district, about 90 km from Patna, on Monday."The cause of his death will be known after post-mortem," Singhal said.Bhojpur superintendent of police Avakash Kumar has suspended the police station officer on charge of negligence of duty.The local police said soon after the body of 19-year-old Bimlesh, who had been reported missing, was found on the railway track, a mob from his village first staged a protest and then attacked a few people living in the adjoining red light area.Some people blamed a woman for the death, police sources said.They said the mob rushed to her house and dragged her to the street. She was beaten up and paraded naked, they said.A police team that reached the spot hours later was attacked by the mob. The police had to open fire to save the woman. Later she was admitted to a local hospital, police sources said.