They used a rope to climb the 22-feet-tall boundary wall of the jail and sneaked out of the compound.

Four prisoners, including two convicted for smuggling drugs and others facing trials in murder and rape cases, escaped from a jail in Madhya Pradesh's Neemuch district on Sunday, police said.

As per preliminary investigation, the four prisoners - Nar Singh (20), Pankaj Mongia (21), both from Rajasthan, and Lekh Ram (29) and Dubey Lal (19) - cut the iron rod of their barrack at the sub-jail located in Kanavati area, just about 5 km from the district headquarters.

They then threw a rope across the 22-feet-tall boundary wall of the jail, climbed it with the help of some outside support and sneaked out of the prison compound, jailor RP Vasunai told news agency Press Trust of India.

Singh, hailing from Udaipur, and Mongia, belonging to Chittor, were earlier convicted under the Narcotic Drugs and Psychotropic Substances (NDPS) Act and facing different imprisonments.

Lekh Ram, a native of neighbouring Mandsaur district in Madhya Pradesh, was being tried in a case of loot and murder, while Dubey Lal, a resident of the state's Mandla district, was facing trial in a rape case, RP Vasunai said.

State Director General (Prisons) Sanjay Choudhary declared a bounty of Rs 50,000 on each of the four.

Top district officials reached the prison to probe the incident.

Madhya Pradesh Police has stepped up security in areas bordering Rajasthan, the official said, adding efforts were on to trace the four prisoners.