Lincoln Prison Governor Lynn Saunders said despite a fall in crime the number of inmates nationally has risen from 43,000 in 1991 to 77,000.

She called for community service and for drug rehabilitation services to be considered rather than prison.

A spokesperson for the Home Office said her comments "are in line with our criminal justice strategy" to use community sentencing where appropriate.

There are people with drug problems who said they come to prison to get drug detox Ms Saunders, Lincoln Prison Governor

Ms Saunders told BBC News that short-term prison sentences do not give her staff the chance to rehabilitate offenders.

The government said last week that it is considering the early release of "a few hundred more prisoners" fitted with electronic tags to cope with severe jail overcrowding.

"We are limited to just coping with the numbers rather than dealing with individuals and trying to help them through their various problems," Ms Saunders said.

"There are a large number of people in prison that shouldn't be there and could be more effectively dealt with in the community."

She said a lot of people in prison are clearly in need of help with "significant mental health issues".

"There are people with drug problems who said they come to prison to get drug detox because they can't get it in the community.

Close scrutiny

"To me this seems a ludicrous waste of resources and money.

"And there are people who simply a few years ago would have not come to prison at all and would have been given a community penalty."

But Cindy Barnett, deputy chairman of the Magistrates Association, said: "All sentences have to consider the seriousness of the offence, that's a matter of statute and of course we have to follow guidance from the Sentencing Guidelines Council.

"There are several purposes of sentencing and certainly reform and rehabilitation is one, protection of the public is another.

"We have to consider all of them in each case.