HATTIESBURG, Miss. (September 7, 2009)--Prisoners injured in the crash of a private prisoner van in southern Mississippi were hospitalized under guard Monday in Hattiesburg, Miss.

The driver was killed and several passengers were injured in the crash Sunday on Interstate 59 in Hattiesburg.

The van was carrying prisoners from Texas and Louisiana to different detention centers along the East Coast when the crash happened.

Police say the van, carrying three guards and nine inmates, veered off the highway, hit an embankment and trees, and then flipped over.

All 12 occupants had to be cut from the crumpled wreckage of the white van, which lay on its roof with its windows shattered amid broken trees.

The van's driver was a 50-year-old security officer for a private prisoner transport agency.

Hattiesburg police spokesman Synarus Green says a guard and two prisoners were in critical condition.

Another security guard and six other prisoners also remained hospitalized with various injuries.

Another prisoner was treated and released to authorities Sunday.