Violence erupted in West Bengal’s Uttar Dinajpur district on Sunday over the death of a teenage girl, PTI reported. Locals, who alleged that the girl was raped and murdered, went on a rampage. They blocked National Highway 31 and set at least three buses and police vehicles on fire.

The protest took place at Chopra area, around 500 km north of Kolkata. The situation remained tense for several hours even as the police used tear gas shells to disperse the crowd. A large number of police personnel, including the Rapid Action Force, were deployed at the site to contain the protestors. The mob reportedly attacked the police with bricks and stones.

The sister of the deceased said she had cleared the Class 10 state board examinations last week and went missing on Saturday night, according to NDTV. Her body was found the next day under a tree. Two bicycles and some mobile phones were recovered from the spot.

The West Bengal Police said the postmortem report stated the case of death as “effect of poison” and there were “no injury marks”. They added that the family did not file any complaint.

“Inquest by a magistrate and videography of the post mortem was done,” the police tweeted. “As per the PM report cause of death is ‘effect of poison’. No injury marks anywhere in the body has been found. There is no sign of sexual or physical assault.”

The local police said the situation was under control and that an investigation has been launched in the case.

The Bharatiya Janata Party alleged that the girl was raped and murdered by a Trinamool Congress leader, according to The Indian Express. “We demand the immediate arrest of the culprits,” BJP National Secretary Rahul Sinha said. “They should be booked and action initiated against them.”

Kanaia Lal Agarwal, TMC district president, denied the allegation and accused the saffron party of trying to instigate people. “There is no political connection to the incident,” he said. “The police are investigating the matter. The BJP is desperately trying to give a political colour to the incident, instigate a section of people and disturb peace.”