A movie producer from Kent has described the nightmare of living with the knowledge his son was a mass murderer.

British-born Elliot Rodger, 22, killed six people and injured 13 others before taking his own life in California last month.

His father Peter, who was an assistant director on Hollywood blockbuster The Hunger Games, studied in Maidstone before moving to the States.

Now he has described how Elliot's family – including his grandmother, who still lives in Smarden, near Ashford – had no idea he was violent.

Mr Rodger has spoken fully for the first time about his heartache over the killing spree in an American television interview.

"Every night I go to sleep and I think of those young men and young women that have died, and who were injured and were terrorised, and my son did that," he told Barbara Walters on ABC’s 20/20 programme.

"My son caused so much pain and suffering for so many families."

Mr Rodger told how his life is like a "reverse nightmare situation", where instead of waking up from a bad dream, he wakes up into a horrible reality.

He also revealed he never thought Elliot "could hurt a flea".

"I mean, this is the most unbelievable thing," he added. "What I don't get is we didn't see this coming at all."

He studied at Maidstone College of Art before moving to America when Elliot was a child.

Elliot went on the drive-by killing spree in his BMW after vowing on YouTube to slaughter women because his sexual advances had been rejected.

The spurned virgin also died from a gunshot wound to the head after the killings while young people were out socialising in a beach-side resort near the University of California in Santa Barbara.

In a chilling video message the day before his attacks, he said he would kill every "single stuck-up blonde I see".

His grandmother Lois Rodger - known as Jinx - earlier described him to KentOnline as "very sick".

The 89-year-old - of Water Lane, Smarden, near Ashford - last saw her grandson in November when she visited the family in California.

A former journalist, she said: "My grandson was a very sick boy. I am still very upset about all this. This is very sad for the whole family."

Mrs Rodger's late husband George was a war-time photographer and the couple lived in Smarden for more than 40 years.

He was the first photographer to enter the Bergen-Belsen concentration camp and later founded Magnum Photos.

Mrs Rodger added: "If my husband was still alive he would be in terrible shock."

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