Lebanon's top prosecutor has charged the judge leading the inquiry into the 2020 Beirut port blast and ordered the release of suspects in custody.
Ghassan Oweidat summoned Judge Tarek Bitar for questioning, accusing him of "acting without a mandate".
But the judge insisted that Mr Oweidat had no authority to charge him.
On Monday, he unexpectedly restarted the probe after a 13-month suspension and filed unspecified charges against eight officials, including Mr Oweidat.
No-one has yet been held accountable for the blast on 4 August 2020, which killed at least 218 people and injured more than 6,000 others.
A fire triggered the detonation of 2,750 tonnes of ammonium nitrate that had been stored unsafely in a port warehouse for almost six years, causing a massive explosion that devastated a large part of the Lebanese capital.