Convicted killer Tony Martin, who shot dead a teenage intruder in his home in 1999, has died at the age of 80, a family friend has said.

The killing of 16-year-old Fred Barras at Martin's Norfolk farmhouse was hugely controversial at the time, with the country divided over whether his actions were pre-meditated, or simply a farmer defending himself and his property.

Martin was jailed in 2000 for the boy's murder, and for injuring another man, 29-year-old Brendan Fearon in the same incident, before being released three years later after the murder conviction was reduced to manslaughter.

Martin lived on his own at his sprawling, semi-derelict farmhouse in Emneth Hungate, near Wisbech on the Norfolk/Cambridgeshire border at the time of the incident.

On the night of 20 August 1999, the pair entered his home, in an isolated part of the village, with the intention of burglary.

They had travelled from Newark in Nottinghamshire that evening to raid the property, called Bleak House, where Martin stored antiques.

The farmer heard them, came down from an upstairs bedroom and opened fire with a pump-action shotgun.

Fred died at the farm while Fearon was treated in hospital for his injuries.

Martin was arrested and charged with murdering the boy.

At his trial, Martin claimed to have been acting in self-defence while prosecutors argued he had anticipated the pair and lay in wait for them.

The case attracted huge public attention, with Martin's supporters casting him as a man taking a stand to defend his home and others seeing him as a violent eccentric who turned vigilante.