Horror filmmaker Norman J Warren has been remembered as a “ground-breaking director” and a “gentle, kind, sweet chap” after his death at the age of 78.

The English director is best known for 1970s horror films such as Satan’s Slave, Prey and Terror, as well as the 1980s works Inseminoid and Bloody New Year.

His manager and friend Thomas Bowington told the PA news agency he died in the early hours of Thursday morning from natural causes, after a year of ill health.

He said: “He was a ground breaking director in the 70s and 80s, after so many films had been in a period setting, he put horror in a more modern setting.

Norman J Warren with composer and collaborator John Scott (Mark Mawston)

“He was the biggest film lover I ever met, he loved films and was so helpful young film makers.

“He was always happy, always laughing, always kind.

“Considering some of his films were quite savage, a gentler, kinder, sweet chap you couldn’t find, he was like everyone’s best friend.”

Warren’s films have been referred to as “New Wave” British horror because of the increase in gore and sexual explicitness following the popularity of the Hammer Horror films previously.

He stopped making feature films in the 1980s and turned his attention to documentaries and educational films, including for the BBC, and Mr Bowington said he was popular with children because of his “lovely, easy-going” nature.

He also made short films, including the silent film Fragment, with his frequent collaborator, the composer John Scott.

He also worked frequently with the screenwriter David McGillivray, who said: “Norman J Warren was my best friend in the entertainment business.

“We met in 1967 when he was making his first feature My Private Hell.

“He was the youngest director of ‘sexploitation’ films in the 60s and went on to try other genres until the 1980s.

“Subsequently his early films have become cult successes.

“He liked nothing more than to attend festivals and convention and talk to fans and young filmmakers and help to prepare for DVD releases.”