Federal Police chiefs on Wednesday called for former Brazilian President Luiz Inacio Lula da Silva to be transferred immediately to a military facility for security reasons.
The request was made by the Federal Police chiefs' union in the southern state of Panama.
It said in a statement that Lula, who governed Brazil from 2003 to 2011 and remains the country's most popular politician, needed to be transferred to a facility that offers "security conditions and does not provoke disturbances and risks for the population and federal officers."
The union said an armed forces lock-up would be the ideal place to hold Lula, who is serving a 12-year, one-month sentence for corruption at the Federal Police's headquarters in Curitiba, a city in the southern state of Parana.
Since the charismatic ex-president arrived at the police headquarters on Saturday night and was housed in a 15-square-meter (161-square-foot) cell, hundreds of his supporters have been camping outside the building and say they will not leave until he is released.
"There are proven risks to the people camping outside the Federal Police building, to federal officers and other members of the Public Security system who live near" the headquarters due to the "invasion" of Lula's supporters, the statement said.
Lula was convicted in July 2017 by crusading Judge Sergio Moro of accepting bribes in exchange for helping Brazilian construction company OAS obtain lucrative contracts from state oil company Petrobras and sentenced to nine years and six months in prison.
On Jan. 24, an appeals court in the southern city of Porto Alegre voted unanimously to uphold that earlier verdict and increase Lula's prison sentence to 12 years and one month.
That same court on March 26 rejected Lula's appeal of its own earlier decision.
The case against Lula, who denies any wrongdoing, is based largely on plea-bargained testimony from people already convicted as part of the sprawling investigation into the $2 billion Petrobras scandal.
Lula leads in the polls ahead of the October presidential election and his Workers Party (PT) says he remains their presidential candidate.
Separately, PT Chair Gleisy Hoffman criticized a judge's decision to place restrictions on Lula's visitation rights.
"The law is a right and not a privilege," Hoffman said in an interview with EFE, adding that Judge Carolina Moura Lebbos' ruling was part of a strategy by Moro to keep Lula isolated.
The country's penal enforcement laws give an inmate the right to receive visits from his/her attorney on any week day and from duly authorized family members and friends on Wednesdays.
But the courts have only allowed the ex-president to meet with his attorneys thus far.
A 2010 Brazilian law signed by Lula states that a defendant whose conviction has been upheld on appeal is barred from competing for public office for eight years.
But Lula, who is expected to register as a presidential candidate on Aug. 15, could ask the Supreme Electoral Tribunal to make an exception in his case.