Image copyright A3 Coalition Image caption The judge ordered Albert Woodfox's unconditional release

The release of a man who has spent more than four decades in solitary confinement will now be delayed after a request by Louisiana's top lawyer.

It means Albert Woodfox's release has been moved from Tuesday evening to, at the earliest, Friday afternoon.

A judge had ordered the 68-year-old to walk free, after his murder conviction was twice overturned.

But the attorney general said prosecutors would appeal "to make sure this murderer stays in prison".

The state now has until Friday afternoon to explain why he should continue to be held in jail.

Woodfox has been in solitary confinement since April 1972, after he was blamed for the death of a guard during a prison riot.

Media playback is unsupported on your device Media caption After being released from solitary confinement, many prisoners find it hard to adjust to life outside of prison

He was tried twice for the guard's death, but both convictions were later overturned. He denies all the charges.

Confined for 23 hours a day, he had only one hour outside his cell to "walk alone along the tier on which his cell is located", according to court documents from a case challenging his prison conditions.

Exercise was permitted three times a week and there were restrictions on "personal property, reading materials, access to legal resources, work, and visitation rights".

Solitary confinement in the US

80,000 prisoners estimated to be in solitary confinement in the US

Held in 44 states, 25,000 in super-maximum security ("supermax") jails

Conditions vary, but can include up to 23 hours a day confined alone

Psychologists warn of negative reactions, such as isolation panic

UN torture rapporteur wants global ban in all but exceptional circumstances

Proponents say needed to protect other prisoners and staff

Sources: ACLU, Bureau of Justice Statistics. Solitarywatch.com, Louisiana Prison Watch

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