A riot among inmates at a prison in Mexico's Pacific coast state of Colima has left nine prisoners dead and seven injured.
The Public Safety Department said the riot on Tuesday originated in a fight between two rival groups of inmates in a cell block.
The department did not say what caused the dispute.
State police, army troops and National Guard personnel retook control of the cell block about an hour later. Officials said several homemade knives and a pistol were found in the cells.
Such disputes are often started by imprisoned members of rival drug cartels. Colima's seaport has long been a hotbed of drug trafficking.
Inmates also frequently exercise a certain level of control inside Mexico's poorly administered prisons, frequently leading to problems.
On January 8, a riot erupted inside the Apodaca prison outside the northern city of Monterrey over prisoners trying to extort money from others, and 56 inmates were inured by rocks and beatings.
Aldo Fasci, the public safety secretary for Nuevo Leon state, said many inmates at the Apodaca prison work in industrial plants and at least five gangs are extorting money from other inmates inside prison walls.
Authorities acknowledge that inmates have been in partial control of the facility.
Australian Associated Press
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