Murderer 'sent threatening letter to victims' family'
Robert Stratton killed Julie McCash and David Sorrie in Dundee after a vigil.
The family of two cousins who were killed after a vigil claim they have received a "threatening letter" from the knife killer.
Robert Stratton killed Julie McCash, 43, and 32-year-old David Sorrie during an altercation in Dundee in February.
Their deaths came after a get-together for the family and friends of 18-year-old Ralph Smith, who lost his life after falling from cliffs in Arbroath, Angus, the previous day.
Stratton was ordered to serve at least 23 years for murdering Ms McCash and the culpable homicide of Mr Sorrie.
Police are now investigating a threatening letter to the cousins' family, who claim it is from Stratton.
A spokesman said: "Police Scotland can confirm it has received a complaint about unsolicited mail and the matter is being investigated."