The home secretary, David Blunkett, is today expected to announce that Yarl's Wood detention centre in Bedfordshire is to remain open, in an attempt to prevent asylum seekers being detained in prison.

Security has been tightened since the fire 11 days ago, which caused an estimated £35 million in damage.

The announcement is expected as new figures show a sharp increase in the prison population.

Early release, electronic tagging and doubling up in cells are among the measures being considered by the home office as the prison population continues to soar.

Since January 11, the number of UK prisoners has risen by 3,130 to a record 69,572, it was revealed. Whitehall predicts that the number will rise to 70,000 in a number of weeks.

The large rise in the female prison population should be considered before jailing women defendants, judges and magistrates have been told by Lord Chief Justice Woolf.