With three attacks a day on meter maids in London, police have taken the extraordinary step of providing protection to meter maids in key ticketing locations. They will provide high-profile escort in areas with the most violent incidents have been reported. Motorists have increasingly taken out their frustrations on traffic wardens, sometimes with baseball bats or other weapons.

Motorists often complain of expensive tickets being issued seconds after a meter expired as overzealous meter maids compete for "performance" bonuses.

In February the wave of attacks was condemned in an official report. It said: "Parking attendants work in difficult circumstances, frequently on their own. "While the outcome of their work is beneficial to London, those receiving penalties are rarely appreciative of this and many are abusive. On average more than three attendants are assaulted every day in London, a shocking statistic."