Four children aged between five and nine years were injured in a crude bomb explosion after they picked up an abandoned plastic packet kept near a playground at Kharashinpur village in Birbhum’s Mallarpur on Wednesday evening.

One of the children with serious splinter injuries was shifted to a private hospital in Durgapur. The remaining three have been admitted to Rampurhat Medical College and Hospital.

Police detained a few suspects for interrogation and informed the bomb squad to be able to get a clear picture of the gravity of the explosion and the types of explosives.

“Three out of the four children are out of danger. We have shifted one of the seriously injured to a private hospital in Durgapur for better treatment. We have started a probe in this connection and detained a few from the local village for interrogation,” said Abhishek Roy, the additional superintendent of police (headquarters) of Birbhum.

Sources said Wednesday’s explosion happened in the backdrop of the extensive drive of the police to recover crude bombs stockpiled in various pockets of the district.

Birbhum has witnessed several political clashes and violence in the recent past such as the Bogtui massacre where 10 persons lost their lives in March last year.

Family members said all the four children were related to each other and had gone to play in a local playground around 4pm on Wednesday.

According to a police source, all the four children were running around, collecting some boxes and plastic packets from an abandoned place when the local people heard an explosion.

“It appeared to be louder than one crude bomb. The sound of explosion was massive. We rushed to the spot and found the children in a pool of blood,” a villager said, adding it was a horrifying sight.

The police said that they had recently recovered hundreds of crude bombs from various places in Birbhum district. The drive to unearth explosives is being carried out to put an end to violence before the panchayat polls, a police officer said.