Alleged Burrabazar don Gopal Tiwari and his 12 associates who had been arrested for plotting an attack and shooting at a police officer in the city on the day of the civic polls in 2015 were acquitted on Thursday for want of adequate evidence.

Judge Somnath Mukherjee of the city sessions court, who delivered the verdict, observing that the police had failed to prove that Tiwari or his associates had shot at sub-inspector Jagannath Mandal, who had taken a bullet on his chest while discharging poll duty in the Girish Park area on April 18, 2015.

Mandal, 59, is now additional officer-in-charge of Kasba police station. He retires at the end of this month.

Despite repeated attempts, Metro could not contact Mandal over the phone on Thursday.

A section of the police expressed frustration and anger at the turn of events. “Does that mean no one shot at our colleague?” an officer asked.

“It’s a sad day for all of us who risk their lives in the line of duty,” another officer said. “If people are acquitted even after shooting at a police officer in the presence of several other cops, it sets a sad and shocking precedent.”

Police had submitted a 261-page chargesheet, which contained statements of 57 witnesses. Tiwari and the other accused were charged with attempt to murder, rioting with dangerous weapons, deterring public servant from performing duty and mischief.

The chargesheet mentioned that Tiwari and some of his associates were within 150m of the spot where Mandal was shot at, around an hour after the poll had ended.

Mandal, then sub-inspector at Girish Park police station, had come under attack while he was trying to disperse a group of Trinamul supporters.

The police made a few quick arrests before rounding up Tiwari from a hotel in Lake Town for allegedly masterminding the attack.

Judge Mukherjee, however, said: Several lacunae were found in the investigation.... There is no evidence that the accused had shot at the police.”

The judge also said the sleuths had failed to prove that the gun that was seized from the accused was used to shoot at Mandal. The seized gun’s forensic and ballistic test reports apparently did not match the bullet found on Mandal.

Tiwari later said outside the court: “All of us were falsely implicated in the case.”