A Catholic priest who inspired The Exorcist died from a fall after what he claims was a possessed child spoke to him, it has emerged.

The new revelation comes from a CIA agent after it had been widely reported Malachi Martin from Ireland told a friend an invisible force pushed him to his death.

Ahead of the release of a new documentary, his close friend Robert Marrow has lifted the lid on the moment he believes the priest was effectively killed - when a possessed four-year-old girl he was meant to be exorcising spoke to him in America.

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A picture of Malachi Martin taken in 1996, three years before his mysterious death

Max Von Sydo playing a priest in The Exorcist (1973), which is said to be inspired by Father Martin

Linda Blair playing the role of a possessed Regan MacNeil in the 1973 cult classic The Exorcist

Talking to RTE Radio 1’s The Ryan Tubridy Show, the producer of the feature-length show called Hostage to the Devil Rachel Lysaght recalled a harrowing moment during filming.

Former CIA agent Mr Marrow retracted the steps to Connecticut where Father Martin had offered to carry out an exorcism on the four-year-old girl.

When he arrived at the neutral home, the family were already there, and the girl walked up to the priest and said: 'So you're Malachi Martin - and you think you can help her?', suggesting she was talking while having an out-of-body experience.

It has been claimed that after the exchange in 1999, a fall led to his death from a head trauma at the age of 78.

He told a friend that it was caused by an invisible force that pushed him.

By this time, the father from County Kerry in South-Western Ireland was hiring himself out as a private exorcist and it is believed he was the inspiration behind the famous film released in 1973.

Malachi Martin, pictured, died of a head trauma after a fall which he described to friends as being caused by a push from an invisible force

A screenshot from Hostage to the Devil, which features former CIA agent Robert Marrow's account of the creepy demise of Father Martin

Due to Father Martin's age, Mr Marrow drove him to his clients across America where he had relocated after turning his back on the church.

The former CIA agent told RTE the encounter between the priest and the girl was the most disturbing thing he had ever seen, according to Rachel Lysaght, who also wrote the new documentary.

It will be available on Netflix from Sunday.

Linda Blair, pictured left in the movie and right in 2000, lost her grandfather on the opening day

Max Von Sydow and Linda Blair in The Exorcist (1973). Both lost relatives on the first day's filming

It is not the first time the 1973 cult classic has been linked to creepy curses.

The Exorcist actors Jack MacGowran, and Vasiliki Maliaros both died while the film was in post-production.

The Exorcist was MacGowran's last film role as the alcoholic director Burke Dennings.

Maliaros, who played Karras' mother, also died before the film was even released - and they both died in New York.

On the first day of filming there were also two deaths to close relatives of the main cast.

Linda Blair, who played the possessed Regan MacNeil, lost her grandfather, and Max Von Sydow, who was freeing Blair from her demons on screen, lost his brother.