Bhopal, May 17 : A tribal couple along with their 12-year-old daughter were found dead on the rooftop of their building in Madhya Pradesh's Mandla district. The incident occurred late on Monday. After getting information, a police team reached the spot and the bodies were sent for post-mortem. As per the police, unidentified criminals killed the three when they were sleeping on the rooftop of their home. The preliminary investigation revealed that the victims were attacked by a sharp weapon as their throats were cut. An FIR has been registered and police teams have begun a search operation for the culprits involved in the murders, said a police official. The deceased have been identified as Narmada Singh (62), his wife Sukarti Bai (57) and their daughter Kumari Mahima (12). "The bodies have been sent for post-mortem and further investigation in the matter is under way. Several police teams are in search of the criminals," said a police official in Mandla district. Former Chief Minister and Congress Rajya Sabha MP Digvijaya Singh has raised questions about the state of law and order in Madhya Pradesh, stating that tribal people are being targeted. "The law and order situation in the state is deteriorating day by day. Atrocities against tribals have risen in Madhya Pradesh. The state Home Minister should resign from his post if he can't handle the situation," Singh said, adding that, "even the Chief Minister does not have the courage to ask for his resignation." /IANS