Troy Kennedy Martin, the screenwriter responsible for Edge of Darkness and The Italian Job, died yesterday of liver cancer.

Kennedy Martin, 77, had a long career as a TV and film writer, beginning in the late 1950s with his first TV play, Incident at Echo Six, for the BBC.

In the early 1960s he created the long-running BBC drama Z-Cars, which broke new ground in the degree of realism it brought to the depiction of a northern police force at work.

Kennedy Martin moved into film writing with The Italian Job, starring Michael Caine, in 1967 and then Kelly's Heroes, a second world war action comedy featuring Clint Eastwood.

His later TV work included Reilly - Ace of Spies, for ITV; and Edge of Darkness, the critically lauded 1985 BBC thriller starring Bob Peck as a policeman who becomes embroiled in an international conspiracy to convert nuclear waste into plutonium.

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