Detectives investigating the deaths of two black relatives have been advised by Scotland Yard's Racial and Violent Crimes Taskforce, the BBC has learned.

West Mercia Police is being encouraged to learn from mistakes in the inquiries into the racist murders of Stephen Lawrence and Michael Menson.

The news comes as one newspaper reports that Stephen Lawrence's parents have fixed on £500,000 as the amount for which they plan to sue the Metropolitan Police over his killing.

At an inquest next month into the deaths of Harold McGowan, 32, and his 20-year-old nephew Jason McGowan, leading human rights barrister Michael Mansfield QC has agreed to act for the family.

Both men were found hanged in Telford, Shropshire. The family's solicitor, Errol Robinson, said both suffered from a campaign of harassment by far-right extremists.

West Mercia Police has already said there was no evidence of anyone else being involved in the men's deaths.

But the BBC's Newsnight programme has learnt that detectives working on the case met with officers from the Met taskforce earlier this week.

It is understood the team - which is encouraging other forces to learn from the Lawrence and Menson cases - told the West Mercia detectives "in no uncertain terms" how they should proceed.

The Chief Constable of West Mercia has been advised to meet and brief the McGowan family on the inquiry and detectives have been encouraged to hold a press conference with the family to try and find more witnesses.

Mr Robinson says Harold McGowan, who worked as a doorman, had become a target for racists after barring a man from a pub. He said he had been warned he was on a "death list" of extreme right-wing group Combat 18.

'Intimidated by racists'

He had been attacked on at least two occasions and endured a two-year campaign of harassment before he was found dead in a friend's home on 2 July 1999, said Mr Robinson.

Six months later, in the early hours of New Year's Day, his nephew Jason - who had recently been married - was found hanged outside a leisure centre.

Friends and relatives said he had been enjoying himself at a New Year's Eve party shortly before he died.

'Internal review'

In the weeks leading up to Jason's death, a family member received an anonymous telephone call warning them to stop investigating the uncle's death.

Mr Robinson has stopped short of saying the two men were killed by racists but added: "Whether some third party was involved cannot be discounted."

A police spokesman told the BBC: "An internal review into the investigation of both deaths has been going on for some time.

"As part of that process the officer carrying out the review is consulting with a number of outside organisations, including the Metropolitan police's Racial and Violent Crimes unit."

The chairman of the West Mercia Police Authority, Brian Watkins, said the force was committed to protect and defend the interests of any minority.