Some 65 workers contracted to the Metropolitan police struck for 24 hours on Friday 23 December in a long-running dispute over pay.
The workers—including plumbers, electricians and fitters—are members of the Unite union. They work for the special events division of support services company Interserve.
There was a Unite picket line at the Met’s headquarters at New Scotland Yard, as well as at Interserve’s main depot in Wimbledon.
Five more strike days are planned for 2012, with the next one set to take place on Friday of this week.