STILLWATER (AP) - A lockdown at one of Minnesota's most secure prisons is easing after a fight broke out among inmates last weekend.

The Minnesota Department of Corrections says it's still investigating the cause of Saturday's brawl. Spokeswoman Sarah Fitzgerald says nobody had been charged as of Tuesday, but the facility was returning to normal operations.

During the lockdown, inmates were required to stay in their cells instead of going to work in the prison or participating in other programs.

By Tuesday afternoon, she says, only the offenders in one housing unit inside the prison remained on lockdown. There are seven housing units inside the prison walls plus a minimum security unit outside.

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