U.S. prosecutors said Wednesday they will not seek the death penalty as part of a plea agreement with the man charged in the political assassinations of the top Democrat in the Minnesota House along with her husband, as well as the attempted murders of a state senator and his wife.

Alabama's plans to execute a death row inmate using nitrogen gas appeared to be thwarted Tuesday by a federal judge permanently blocking the state from using that method, declaring it violates the constitutional ban on cruel and unusual punishment.