Each cell block houses up to 50 prisoners with several guards stationed outside each block.
Deputy Police Commissioner Auapa'au Logoitino Filipo told Radio Polynesia more than 60 police and fire and emergency services officers responded to the call for help from the prison.
All prisoners have been accounted for and Auapa'au says police have launched an investigation.
It’s been more than a month since prisoners were allowed visitors because of the nationwide Covid lockdown.
Photo file RNZ Pacific Caption: Tanumalala Prison in Samoa