Author David Yallop, who fought for Arthur Allan Thomas release, dies aged 81

Author David Yallop - famous for his work around the controversial Crewe murders - has died.

Yallop died in London, aged 81.

Stuff reported that Yallop's family had released a statement confirming his passing.

The British author published the book Beyond Reasonable Doubt about murders of Harvey and Jeanette Crewe in their Pukekawa home in 1970.

His work led to the man convicted of their murders - Arthur Allan Thomas - being released from prison.

The book, later made into a movie of the same name, cast huge doubt on the evidence used to convict Thomas of the infamous double murder.

Thomas was eventually granted a Royal pardon.

His family statement reportedly said he had suffered from Alzheimer's disease in recent years.

Yallop's death follows the passing of Kiwi journalist Pat Booth, who also wrote extensively on the Crewe case.

Booth, who as Auckland Star assistant editor broke the case open when he uncovered police had planted the rifle shellcase - the key to Mr Thomas' conviction - in the Crewes' garden, died in January.