Screenshot of video showing IAS officer beating up a youngster.

An IAS officer in West Bengal and his wife have been caught on camera thrashing a young man at a police station, allegedly because he had posted "objectionable content" on the internet about her. The officer has been sent on leave after the video went viral.

Nikhil Nirmal, the district magistrate of Alipurduar district, is heard on video threatening to kill the youth.

The video of the incident, which took place yesterday, has provoked outrage.

According to police sources, the young man, Vinod Kumar Sarkar, had posted some objectionable comments about the officer's wife, Nandini Kishan, on social media.

A police complaint was filed at the Falakata Police station and Sarkar was arrested.

On Sunday, the District Magistrate and his wife arrived at the police station. In front of the police station in-charge Soumyajit Roy, the officer brutally beat up the young man.

Sarkar begged for forgiveness but there was no stopping the angry couple. Ms Kishan is even heard asking the police to get a "lathi". A policeman says "a lathi cannot be used."

The officer tells Sarkar: "In my district, no one speaks against me. If I can put you in jail in half an hour, I can also go to your house and kill you."

Ms Kishan said, "Someone has given you the idea to say all this. Who was it?"

She took out her phone, pulled up whatever Sarkar had written and ordered him to read it aloud. The youth did not. She then asked him, "what is my name?" The youth kept quiet. Then she started slapping and kicking him.

Finally, a policeman took the accused man away.

Jatishwar Bharati, a member of the Jalpaiguri unit of the Association for the Protection of Democratic Rights (APDR) said, "The district magistrate is the head of the district. It was wrong of him to enter a police station and thrash the youth. If someone has abused his wife on social media, he should have got the cyber-crime police to investigate."

"Police would act according to law. But to take his wife and go to a police station and assault the accused and threaten to kill him cannot be tolerated," he added.

The district magistrate was not available for comments on phone, though some reports state he has denied that the incident took place.