ONE of Scotland's most notorious killers has died at the age of 73.

Angus Sinclair, known for the infamous World's End murders, was convicted of killing four people, though he was suspected of having killed at least four more.

Sinclair had been serving time in prison since 1982 following a series of rapes on children.

READ MORE: Profile: The Scottish serial killer who spent most of his life behind bars

It was only five years ago that he was finally convicted for the murders of Helen Scott and Christine Eadie, two teenagers last seen at the World's End pub in Edinburgh in 1977.

Speaking with the BBC at the time, detectives said they believed he had killed four more women over a seven month period, but they couldn't prove it.

He was handed the longest ever sentence by a Scottish court; a minimum of 37 years in prison.

Sinclair's first victim was his seven-year old neighbour Catherine Reehill, who he raped and strangled in 1961 when he was just 16 years old.

He called the ambulance himself, claiming that "a wee girl has fallen down the stairs".

He served just six years in prison.

Sinclair was released in his early 20s before taking up a trade, getting married and having a son.

In 1977 there was a series of murders across central Scotland. During that time, six young women disappeared in nights on.

Their bodies were discovered on deserted farmland and waste grounds.