"A crisis unit is acting within the institution, as well as the management of the penitentiary administration of the Ministry of Justice," the prison administration added in a statement.
The hostage-taker is reportedly a repeat offender, sentenced to a considerable jail term. The prison administration, however, has stated that the individual "is not incarcerated for acts of terrorism."
According to the agency AFP, "the dialogue has not been terminated", and the security forces, including the regional teams of intervention and security (ERIS), are continuing with their operations.
Later the Justice department stated that the nurse had been liberated after three hours, without any physical injuries.