Q&A: The unanswered questions

Home Secretary Charles Clarke is facing calls to resign over the release of 1,023 foreign prisoners before they were considered for deportation - but what are the questions that still need to be answered about the scandal?

What has happened to the missing inmates?

The problem is they could be anywhere. Many of those facing deportation on release have probably gone to ground. The Home Office knows most of the names, but not where they are and it is critical they find the most dangerous as soon as possible.

How did it happen?

It seems that the Prison Service failed to flag up its foreign national inmates. Files were lost and the foreign prison population increased sharply.

The immigration service failed to start deportation proceedings against the foreign inmates before they were freed.

Barrister Keith Best, of the Immigration Advisory Service, says he believes the immigration service has been overwhelmed with work. He says: "I suspect it was sheer inefficiency and, I believe, a lack of real incentive, amongst people who are in a department that has been battered from one scandal after the next, who actually lost interest in their jobs."

So who is tracking the missing prisoners down?

On Tuesday the police were given the first batch of names. The hope is that some will come up on the Police National Computer.

The checks will reveal if police have current addresses for the missing criminals, and whether any have committed further crimes since their botched releases.

Could it happen again?

To try to prevent this, immigration officers have been put into 60 prisons to help identify foreign prisoners.

Lord David Ramsbotham, chief inspector of prisons between 1995 and 2001, says someone should be put in charge of those prisoners.

"It wants to be directed and managed so that every person going to work every day knows what their job is and knows to whom they are responsible for doing that job," he said.

But it appears that the overwhelming impression emerging from this blunder is of two services - immigration and prison - who are over-burdened, unfocused and some might say, badly managed. It is suggested that until the home secretary addresses the wider issues facing them, then his problems can only get worse.