Patna: Two undertrial prisoners on Tuesday exploded bombs inside their prisoners' van on the busy New Bypass Road in the state capital in an escape bid that failed.

The incident occurred around 1.30pm when a van was carrying the undertrial prisoners to the Beur Central Jail from Patna City court.

Two of the prisoners in the van set off the bomb in the running vehicle near the Dasratha turning. The two prisoners - facing charges of murder, extortion and loot - also tried to open fire with a country-made revolver.

However, the security personnel overpowered the duo and the driver managed to take the van to the jail premises 1.5 km away.

Sources said that the duo was identified as Monu and Sikandar, and they had hatched the conspiracy to escape from judicial custody.

Monu, saources said, is an active member of the outlawed PLFI (People's Liberation Front of India) and was involved in the Bahadur housing colony blast in 2015.

Beur jail superintendent Rupak Kumar said that 18 prisoners were sent to the Patna City court and all the prisoners returned to the prison safely.

The police didn't rule out Maoists involvement behind the plan to set the prisoners free. Over 200 notorious gangsters and Maoists are lodged in the Beur jail.

The police denied reports that an undertrial prisoner and a constable were injured in the bomb explosion.

Patna senior superintendent of police (SSP) Manu Maharaaj said that one country-made revolver, one live bomb of low intensity and other incriminating articles were seized from the van.

SSP Maharaaj has recommended disciplinary action against all the 23 police personnel, including six officers, who were deployed at the Patna City sub-divisional court to ensure foolproof security during the undertrial prisoners' production in court.

"The lapses on the part of the policemen will not be tolerated," the SSP said. "Stern action will be taken against them. At the same time, those policemen who foiled the attempts of some prisoners to escape will be suitably rewarded." Maharaaj later visited the jail and inquired about the incident.

"A detailed investigation will be conducted. Security in the prisoners' vans carrying the UTs (undertrial prisoners) to courts has been beefed up after today's incident," he added.

Patna zone inspector-general of police (IG) Nayyar Hasnain Khan said that 13 members of the district armed police and nine personnel of the special auxiliary police (SAP) had been suspended with immediate effect. Services of six home guard jawans, who were deployed at the city court, will also be terminated.

IG Khan has also asked SSP Maharaaj to monitor the activities of police officials assigned to check court lock-ups.

"It is also being ascertained how the bombs and illegal firearms reached the prisoners travelling in the van," he said.