A deadly riot broke out during family visiting hours Thursday at a prison in the violence-plagued state of Sinaloa in northwestern Mexico, state authorities said.

The violence occurred Thursday morning at the El Castillo Penitentiary in the port city of Mazatlan.

Sinaloa's Public Security Secretariat said on X that nine inmates and one family member were killed in the incident, while 16 prisoners were taken for medical treatment after being injured.