An official from the forensic team that is investigating the bombing at a West Bengal school, informed on Monday, September 19, that they collected samples from the site of the school building where a crude bomb exploded. Four persons have already been arrested in connection with the case. "We have collected some samples and those would be sent to the lab," an official said, as per a report by PTI. The crude bomb exploded on the roof of the school building located in the state's Titagarh area on September 17.

The incident occurred when classes were in progress. The police informed that there was no casualty, as students and teachers were in rooms located on the first two floors of the three-storeyed building. The four arrested are teenagers, aged between 18-19 years. They were arrested from Kamarhati and Titagarh areas around midnight on September 18, the officer of Barrackpore Police Commissionerate said.

BJP has demanded a National Investigation Agency (NIA) probe into the explosion. The issue has taken a political turn as well, with BJP and TMC pitted against each other regarding the state of the education sector in West Bengal.

"We are trying to explore all possible aspects by interrogating them. One of the arrested hails from Kamarhati while the rest are from Titagarh," the officer of Barrackpore Police Commissionerate said, as per PTI. Preliminary investigation revealed that the accused had changed their initial plan to hurl a powerful crude bomb at the school gate, as the spot was crowded. "They climbed onto the roof of an adjacent building to carry out the act," a police official informed.