A 25-year-old man in a fit of rage killed his father by biting deep in the neck and then chopping off his private parts, police in Maharashtra's Nagpur said on Sunday.

The incident happened on Saturday night in the city's Hudkeshwar area and the man, identified as Vikrant Pillewar, was behaving so violently that it took a lot of effort on the part of the police to pin him down, said an official.

"According to the family, Vikrant went into a violent rage without any provocation, and bit his father, Vijay, so hard on the neck that blood started oozing out. He then dragged the 55-year-old into the verandah and chopped off his private parts, killing him on the spot," said the official.

"Vikrant, a gym trainer, was reciting Hindi film dialogues and exhibiting inexplicable behaviour during the incident, the family has said. He also threatened his mother and sister when they tried to intervene. It took five policemen to pin him down and tie him up," said Inspector

Rajkamal Waghmare of Hudkeshwar police station.

He has been charged with murder, the official added.