Police are yet to take action against a Citu leader accused of threatening a traffic cop for booking two bus drivers involved in a mishap under a non-bailable section of the IPC.

Shyamal Dasgupta, a leader of the Citu bus union, had called up officer S. Samaddar of the traffic department’s fatal squad on his cellphone on Tuesday and told him that he would be mowed down by a bus or attacked at home, said police sources.

On July 30, Samaddar had taken up the investigation of an accident the previous day at Shyampukur. An elderly man was injured after being caught between two racing private buses. The local police took the man to hospital and booked the two drivers — Jadav Kundu and Surajit Mallik — for reckless driving. The duo were granted bail.

“The fatal squad took up the case after the man died the next day. Samaddar found it was a case of reckless driving and the drivers’ bail was cancelled. They were arrested and charged with culpable homicide not amounting to murder and remanded in jail custody for 14 days,” said an officer.

The sources said Samaddar had informed his superiors of the threat. “But no action was taken against the Citu leader. Only a general diary was registered on the incident,” said a cop.

Deputy commissioner (traffic) Dilip Banerjee refused comment when asked why no action was initiated.

Sources at Baguiati police station, under which the officer’s residence falls, said cops had been asked to keep an eye on Samaddar’s house. “Since the caller had threatened that Samaddar might be attacked at home, we are keeping an eye on his house,” said an officer.

Dasgupta was not available for comment. The union has been at loggerheads with the police since July 2008, when cops started booking killer drivers for culpable homicide, a non-bailable offence and carries harsher punishment. Earlier, rogue drivers were charged with the relatively lenient section of “causing death due to negligence”.