BEIRUT (AP) — The lead judge investigating last year’s massive blast in Beirut’s port suspended his work in the case Monday after he was formally informed that a former Cabinet minister had submitted a request to recuse him.

Judge Tarek Bitar, the second judge to lead the complicated and thorny investigation, cancelled the questioning of a former military intelligence general, scheduled for Monday. The Court of Appeals now has to decide whether to dismiss him from the case or not.

The development comes amid a growing campaign by Lebanon’s political class against Bitar, who took over the job in February after his predecessor, Fadi Sawwan, was removed following similar legal challenges by senior officials he had accused of negligence that led to the blast.

On Aug. 4, 2020, hundreds of tons of ammonium nitrate, a highly explosive material used in fertilizers that had been improperly stored in the port for years, exploded, killing at least 214 people, injuring more than 6,000 and devastating nearby neighborhoods.

Bitar’s removal, if it happens, would likely be the final blow to the probe, making it highly unlikely that a third judge would take up the job amid threats by members of the country’s political elite who have closed ranks in their effort to block the probe.

Families of the victims of the explosion have already demanded an international probe, not trusting the Lebanese probe. Lebanon is known for a culture of impunity that has prevailed for decades, including among the entrenched political elites.

Bitar's demise began in July when he announced intentions to go after senior Lebanese officials, and summoned for questioning then-outgoing Prime Minister Hassan Diab, three former Cabinet ministers and top security officials.

None showed up for questioning; the parliament failed to lift immunity of those summoned — a necessary step before any prosecution — while Diab's office and then-interior minister, Mohamed Fehmi, declined to let Bitar question the heads of two security agencies.

On Friday, former Interior Minister Nouhad Machnouk, who was also implicated in the probe, filed a motion to dismiss the judge.