Casualties from crashes involving Thames Valley Police cars - such as the one in which Oxford student Emily Higson was killed - have risen in the last year.

Home Office figures show there were 135 casualties between April 2003 and March 2004.

The accident rate is up from the previous year, when there were 131.

But the number of fatalities fell from three to two and the number of serious injuries dropped from 13 to 11.

The other accidents resulted in only minor injuries and the overall increase was much smaller than the 60 per cent rise in collisions nationally.

Thames Valley Police refused to comment on the figures.

The figures are for the whole of Thames Valley -- there is no breakdown for Oxfordshire.

The Police Federation, which represents rank-and-file officers, blamed the rise on poor levels of training.

President Jan Berry said: "We have repeatedly warned training standards have been in decline."

The officer who was driving when Ms Higson was killed in Cowley Road, Oxford, was later cleared of causing death by dangerous driving.

Two weeks ago, a police car answering an emergency call veered across oncoming traffic after a collision with another car and crashed into shops in London Road, Headington, Oxford.

This incident is not included in the Home Office figures.