A 25-year-old man died after an explosion near Madhyamgram railway station early on Monday in what police describe as a low-intensity blast possibly caused by the mishandling of an electronic device.

Sachchindra Mishra, who was from Uttar Pradesh and worked in Haryana, was walking along the Madhyamgram rail bridge around 1.10am when the contents of a bag he was carrying exploded. He suffered severe injuries and died hours later at a hospital.

“The forensic team has visited the spot and collected samples. They will be able to tell the exact nature of the explosion after a proper assessment. But prima facie, it appears to be a low-intensity blast, possibly due to mishandling of some kind of electronic gadget,” said Barasat superintendent of police Pratiksha Jharkhariya.

The police found a mobile phone charger on Mishra and said call detail analysis revealed he had been in the Madhyamgram area since arriving in Calcutta on Saturday. However, they have not been able to determine where he was heading or who he was meeting.

Investigators said they found links between Mishra and a woman who lives in Madhyamgram. “They met on social media. She possibly had a relationship with someone else, and Mishra had come with the intention of preparing an explosive device. He was employed in a Haryana glass factory. We suspect he brought the raw materials from there,” an officer said.

The explosion occurred at a sensitive location between the railway station and Madhyamgram High School, shattering the school’s notice board. The incident has raised security concerns among local residents, particularly because no one in the neighbourhood could identify the victim.

“I cannot imagine what could have happened had the explosion occurred during the school hours or when the railway station is busy with commuters,” said a resident.

Following protocol for any explosion, a team from the National Investigation Agency visited the site. The Bengal Special Task Force, which is expected to take over the case, visited the site later in the day.

The incident has drawn political attention, with the leader of the Opposition in the Assembly, Suvendu Adhikari, accusing the state government of failing to learn from previous security lapses.

Trinamool Congress leader Jay Prakash Majumdar countered that railway protection forces should have been monitoring such incidents near the station.