At least 15 people have been killed after violent clashes erupted in a prison in the Brazilian state of Amazonas on Sunday.
Officials said clashes broke out around 1500 GMT during visiting hours at the facility.
An investigation into the incident is currently underway, with officials adding that "there had never been deaths during the visits".
Senior officials said their speedy reaction helped reduce the fatalities.
In 2017, the prison was the scene of an inmate uprising that ended with 56 dead.

Saudi Arabia orders Iranian military attache, embassy staff to leave
Trump says US considering 'winding down' Iran war; Natanz nuclear facility attacked
Ukraine says talks on resolving war to continue in US on Sunday
Former FBI chief Robert Mueller dies aged 81
Ukrainian shelling kills four in Russia's Belgorod, governor says
