Lebanon's Ministry of Justice on Friday appointed Judge Tarek Bitar to lead the investigation into the Beirut port blast.
On Thursday the Lebanese court of cassation dismissed Judge Fadi Sawan from the investigation after a request by two former ministers he had charged with negligence.
The dismissal sparked anger amongst the families of the victims of the blast who saw it as a setback to their campaign to hold those in power to account over negligence.
On 4 August, the Lebanese capital Beirut was rocked by a powerful blast that could be felt as far away as Cyprus. The explosion was caused by 2,750 tonnes of ammonium nitrate which had been stored insecurely at the port for many years.
Nearly 200 people died as a result and more than 300,000 were left homeless.