Car brakes were allegedly tampered with as part of attempts to intimidate a key new witness in the investigation into the loyalist murders of two Catholic workmen nearly 20 years ago, the High Court has heard.
A sympathy card containing a bullet was also sent to his brother, prosecutors said.
Details were disclosed as Mark Campbell mounted an application for bail.
The 42-year-old, of Canning Place in the city, was arrested and charged earlier this month with the murders of 24 year-old father-of-one Gary Convie and 44 year-old father-of-six Eamon Fox in 1994. All of the alleged offences are denied.
Mr Justice Horner reserved his decision on the bail application.