Kolkata: At least seven passengers were injured in the wee hours today when a crude bomb exploded inside a compartment of Sealdah-Krishnangar local train near Titagarh station in West Bengal’s North 24 Parganas district. The blast took place at around 3:55 am in the fifth compartment from the engine of the local train under Eastern Railway’s Sealdah Main section, injuring seven to eight passengers sitting around, a railway official said. All the injured were rushed to a nearby hospital. According to the official, the rivalry between two gangs could have led to the incident. The railway police were investigating the incident.