A convoy of police cars and motorbikes were out in the city yesterday as part of a motorcade training exercise.

Unmarked vehicles with blacked-out windows travelled through the city flanked by squad cars and motorcycle outriders.

Traffic was stopped as the motorcade, with lights flashing, passed through the city centre.

Leicestershire police would not confirm the nature of the training, which involved helicopter support. It is two weeks until the Queen and the Duchess of Cambridge make an official visit.

Scores of people looked on as the convoy passed through the city and along Welford Road.

One eyewitness said: "I was stopped at some green lights by police cars and bikes while this convoy came through.

"They were driving pretty fast."

A police spokesman said: "Officers were engaged in motorcade training, an essential activity."

The Queen starts her jubilee tour in Leicester on Thursday, March 8.