Dozens of demonstrators gathered outside Lebanon's justice palace on Thursday to protest steps taken this week to hamstring a probe into the deadly 2020 Beirut port blast.
The judge investigating the explosion announced on Monday he was resuming his probe after a 13-month suspension caused by legal complaints and high-level political pressure.
But the country's top public prosecutor objected, saying Judge Tarek Bitar did not have the authority to circumvent the complaints. He filed charges against the judge and released the remaining detainees still held over the investigation.
Families of those killed in the blast, members of parliament and other Lebanese flocked to Lebanon's justice palace to demand Bitar be allowed to continue his investigation.
"This is a judicial scandal," said Ali Abbas, a lawyer who was protesting on Thursday.
"Families of the victims are being wronged - there is complete disregard for this crime," he told Reuters.
Lebanon's Supreme Judicial Council is set to meet on Thursday afternoon to discuss developments in the port blast investigation.
Families of the victims said they feared the country's most senior judges could decide to remove Bitar from the case or appoint a supplementary judge that would effectively sap Bitar's power.
Bitar told Reuters on Wednesday that top prosecutor Ghassan Oweidat "had no right" to file a charge or release detainees because Oweidat himself was charged over the explosion.
Oweidat also issued a travel ban against Bitar and a decision saying the judge did not have the authority to resume his investigation. Both documents were seen by Reuters.
This week's developments set up a tug-of-war in Lebanon's judiciary, which is prone to political influence with many appointments determined by politicians.
The explosion, one of the largest non-nuclear blasts on record, was caused by hundreds of tonnes of ammonium nitrate unloaded at the port in 2013.