Supporters of former Brazilian President Luiz Inacio Lula da Silva wear a T-shirts with Brazilian national colours and Lula's name, in front of the Federal Police headquarters in Curitiba, Brazil, July 8, 2018. REUTERS/Geraldo Bubniak

SAO PAULO (Reuters) - Brazilian federal prosecutors have asked the chief justice of the TRF-4 appeals court, Carlos Eduardo Thompson Flores, to rule on keeping former President Luiz Inacio Lula da Silva in prison, court filings showed on Sunday.

The prosecutors’ request aimed to settle the legal uncertainty created by an injunction granted by a judge on the court who ruled in favor of freeing Lula so he can campaign ahead of an October presidential election.