Bhopal, Sep 1 : Authorities in Madhya Pradesh are suspecting that the murders of three security guards in Sagar district carried out in a similar manner, were a case of serial killing. A total of four security guards were attacked. While three of them died, one has been hospitalised in Bhopal. The attacks had an identical pattern -- smashing heads with a hammer, stones and spade. Noticing the pattern, the police have deployed teams to nab the perpetrator of the attacks which have led to panic among the people in Sagar district. Director General of Police (DGP) Sudhir Saxena has personally started monitoring this case, a senior official told IANS on Thursday. "Four teams of police have been deployed. The DGP himself is monitoring the case personally and giving instructions to senior police officials," the official in the police headquarters in Bhopal, said. While the first case was reported in May, the second took place on Monday and the third and fourth were carried out on Tuesday. The first victim was identified as Uttam Rajak, while Sambhusharan Dube and Kalyan Lodhi were killed on Monday and Tuesday, respective. Mangal Ahirwar is currently in the hospital with skull injuries. The police have noticed that every attack took place in the dead of the night and the victims were picked randomly sleeping in the premises of houses or buildings. They were hit on the head with a blunt object, hammer and spade in two cases. The cases were linked after the mobile phone of the second victim was found near the third in separate police station areas. Despite all the attacks taking place under different police station areas, the similar pattern used made the district police to suspect the involvement of a serial killer. In the wake of the attacks, residents on Wednesday took to the streets and staged a roadblock demanding capital punishment for the accused. /IANS