A riot broke out at a medium-security men's prison in Indiana, according to the mayor, and pictures taken from television helicopters showed at least two fires burning in the courtyard.
Indiana Department of Correction spokeswoman Java Ahmed confirmed there was a disturbance at the New Castle Correctional Facility, about 43 miles (69 kilometers) east of Indianapolis. She said more than one cell house was involved, and two staff members were injured.
The Department of Corrections sent emergency squads and county and state police to the prison. New Castle Mayor Tom Nipp said the entire city police force had also been activated. Helicopter pictures showed officers in riot gear standing outside the prison fence.
The prison is managed by the GEO Group Inc., based in Boca Raton, Florida, according to the Indiana Department of Corrections Web site.
The prison, built in 2002, can house about 2,200 inmates. It currently has about 1,000 prisoners from Indiana and 630 from Arizona.
In March, Arizona and Indiana reached an agreement on housing up to 1,260 Arizona inmates.
Arizona Department of Corrections spokeswoman Katie Decker said at least some of the transferred inmates had complained about being moved, a step that was necessary because of the state's shortage of prison space.
"They're obviously resentful because they had to leave the state," she said, adding that it was too early to say whether the transfers played any role in the riot.
Decker said the inmates sent to New Castle were "carefully picked" before being transferred and could have "no predisposition to violence."
The prison housed an average daily population of 450 in 2005, according to the DOC web site. It also has a psychiatric facility that treats inmates who are bused in from other prisons.
GEO Group last year contracted with the Indiana Department of Correction to assume management of the prison.