Judge Tarek Bitar, who resumed the inquiry on Monday after being impeded by high-level political resistance, charged Prosecutor General Ghassan Oweidat over the explosion, which killed 220 people, Reuters reported.
But the stand-off in Lebanon's heavily politicised judiciary took a fresh turn when Mr Oweidat informed Mr Bitar via letter on Tuesday that the investigation remains suspended. The letter, which a judicial source with knowledge of the situation told The National was authentic, was shared online. Mr Oweidat told The National that Mr Bitar had not informed him of anything, later telling AFP that he had only learned of Mr Bitar's decision "through the media".
Mr Bitar has also charged Hassan Diab, prime minister at the time of the blast, and two other former ministers with homicide with probable intent, court summons stated.
He reopened the investigation on Monday, citing legal studies that challenged its suspension. The investigation has been blocked since late 2021 amid legal challenges from top politicians Mr Bitar wanted to question over the explosion.
Mr Bitar has also charged two high-ranking security officials — the head of General Security Gen Abbas Ibrahim and the head of State Security Gen Tony Saliba.
Mr Bitar has set interrogation sessions for February. Those wanted for questioning also include Jean Kahwaji, the army commander between 2008 and 2017.
On Monday, Mr Bitar ordered the release of five detained suspects.
Mr Bitar has been derided by his critics, including Iran-backed Hezbollah, as politically motivated and close to the US ― although they have not offered evidence to back up this claim. But supporters of the judge, including many of the families of the victims, want him to continue on in the push for justice.
"We've been waiting for this for maybe one year and two months," said Mariana Foudalian, referring to Mr Bitar resuming the investigation. Ms Foudalian lost her 29-year-old sister Gaia in the 2020 explosion. "We all know they were trying to do everything to stop the judge from working," she told The National.
"It's very important that the judge continues. But we will never stop, we will never get afraid, we will continue until the end, until we get justice."
The blast, which injured thousands and levelled or damaged much of the city centre, came after a stockpile of ammonium nitrate — which had been stored at the port for years — caught fire.
The explosion is regarded as a result of decades of mismanagement and corruption in Lebanon, currently grappling with one of the worst economic collapses in modern times.
While numerous officials have admitted to knowing about the ammonium, they claim they requested other officials remove it or make it safe with no clear indication of where final responsibility lay.
"We, in the international community have made it clear since the explosion that we support and urge Lebanese authorities to complete a swift and transparent investigation into the horrific explosion at the Port of Beirut," said Ned Price, US State Department spokesman, on Monday.
"The victims of this explosion in August of 2020 deserve justice. Those responsible must be held accountable."