A serious crash in the police computer system for checking fingerprints has hit investigations into thousands of crimes.

All 43 forces in England and Wales were affected by the shutdown.

The failure was revealed in a leaked memo from Bruce Grant, the head of Scotland Yard's fingerprint bureau.

David Davis, the shadow home secretary, said: "This is yet another in a long line of government IT disasters. It is outrageous, given the importance of this sort of problem to the debate on ID cards, that the government kept it secret."