The move appears to dim prospects for a much-delayed pension reform bill, which would require a change to the constitution. Constitutional amendments are banned during federal interventions.
Eun?cio de Oliveira said the government would appoint an army general to oversee security forces in the violence-plagued state, including the police, and the fire and intelligence departments.
Sources at the presidential palace told Reuters on Thursday the government was considering creating a new ministry to oversee public security.
Legislation to streamline Brazil's costly social security system has been lined up for a first crucial vote in the lower house of Congress next week.
It is being watched closely by investors worried about the government's ability to bring a huge budget deficit under control and avoid a further credit rating downgrade.