A traffic warden in Mumbai has been arrested for allegedly assaulting documentary filmmaker and winner of the Green Oscar award, Nikhil Niranjan Alva.

Nikhil Alva is the son of Congress politician Margaret Alva, who is in charge of Maharashtra at the All India Congress Committee.

According to Nikhil's statement recorded at the Andheri police station, he was travelling on the Western Express Highway on Sunday when he saw warden Lavkush Duby beating up a taxi driver.

The taxi driver had jumped a traffic signal.

Nikhil started recording the altercation with his camera phone, the statement says.

When Dubey saw Nikhil recording his alleged assault on the taxi driver, he turned his attention to the filmmaker and assaulted Nikhil, the police statement says.

An assistant inspector, a head constable and a constable were present nearby but they did not interfere, according to the police statement.

By then state Medical Education and Higher and Technical Education Minister Suresh Shetty had been informed about the incident and he reached the spot.

A case was later registered against Duby under section 323 (voluntarily causing hurt) of the Indian Penal Code, section 341 (wrongful restraint), and section 506 (criminal intimidation) and the warden was arrested.

Sources close to Alva on Wednesday denied that he uses a camera phone.

"It is a high profile case. Top officers have requested that the assistant inspector, head constable and the constable be suspended for not taking any action against the warden," a police source said.