Gaurav Tiwari was found at his Dwarka flat in northwestern India under what has been reported as "mysterious circumstances".

It has led to new claims that as many as "dozens" of other UFO investigators have died in suspicious circumstances over the years.

The Times of India reported that Mr Tiwari's death was treated as suicide.

But relatives say as a newly wed he had no reason to end his life and that he seemed normal in the run up to his death.

According to father, Uday Tiwari, he was drinking coffee with his wife when there was a loud thud from the bathroom.

They found him unresponsive on the floor and he could not be revived.

Police said a black line was found around his neck, leading to a conclusion of asphyxia.

Another theory was he fell hitting his head and inflicting a fatal wound.

An autopsy is due, with an inquest, also being awaited.

Mr Tiwari senior, did however, reveal that his son told his wife weeks before his death “a negative force was pulling him towards it.”

The grieving dad said: "We don’t believe in ghosts etc, but his death has left us shocked and puzzled.”

His son had founded the Indian Paranormal Society, and took part in regular TV shows.