Belgian police have imposed a news blackout after Nicholas Mockford, 60, was shot as he left an Italian restaurant in Neder-over-Heembeek, a suburb of the capital.
The executive was shot three times, once as he lay on the ground, after leaving the Da Marcello restaurant in Rue de Beyseghem at around 10pm on Oct 14.
His wife, Mary, was left beaten and covered in blood. Mr Mockford died on the way to hospital.
Witnesses said they saw the couple walk across the street to their car, a silver Lexus 4x4, before shots were fired.