The murder of a detainee by another inmate "provoked a brawl" inside the facility in coastal Guayaquil city, according to prison director Alfredo Munoz.

Five of the victims have been identified while the sixth remains unknown because his corpse was "incinerated", added Munoz, who was stood down by the government after the incident.

Authorities did not report the number of inmates injured in the violence.

Family members of the prisoners later protested outside the prison to demand information about their relatives, according to images broadcast by local media.

The government of Ecuador decreed a state of emergency in the prison system in response to a wave of fatal violence and severe overcrowding.