The family of two black men who were found hanged have joined detectives in an appeal for information about the deaths.
Relatives of doorman Harold "Errol" McGowan, 34, and his nephew Jason, 20, told a press conference in Telford, Shropshire, that they believed the men may have been murdered by racists.
The head of the Metropolitan Police's racial and violent crime taskforce, Deputy Assistant Commissioner John Grieve, and West Mercia Police Detective Superintendent Mel Shore joined the family in an appeal for information.
Mr Grieve said the deaths posed "a series of unanswered questions" and were now being investigated on the initial presumption of foul play.
Mr Grieve, who said he was unsure if the men were murdered, added: "Foul play unpacks as murder, manslaughter, complicity in another person's suicide or obstructing the coroner."
The McGowan family claims police assumed the hangings were suicides. Harold was found dead on July 2 last year and Jason was found hanging from railings on New Year's Day.
Jason's widow Sinead McGowan urged people in Telford not to be "bystanders" during the police inquiry and to contact officers if they had any information.
Mr Shore appealed for information about two people said to have visited Errol's Telford home on the day he died.
"Obviously, these people are crucial to our investigation. So far they have not come forward."
He added that detectives were anxious to establish Jason McGowan's movements after he left a Telford pub on New Year's Eve.
Officers need to "fill in" the hours between when Jason left the pub shortly before midnight and when he was found hanging from railings at about 6am on New Year's Day.
According to some members of their family, both men had suffered death threats and harassment from far-right groups.
The dead men's family earlier this year met Home Secretary Jack Straw to discuss alleged police mishandling of the investigation.
The family were told in February that Mr Grieve would provide "support and advice" to West Mercia officers, who have failed to find any evidence of foul play.
Robert King, the father of Jason McGowan, has said his son took his own life and urged an end to "lies and rumours" that he was killed by racists.