A criminal investigation against the Russian mercenary leader, Yevgeny Prigozhin, is being reported at Moscow, contradicting the terms of the agreement brokered by Belarus’ president, Aleksandr Lukashenko, and raising questions about Prigozhin’s future.

The reports are emerging in the Russian press following the abortive march toward Moscow of an armed column of the Wagner group on the weekend toward Moscow. Mr. Prigozhin left Rostov, the city his Wagner fighters occupied, like a conquering hero.

Despite shooting down several Russian fixed-wing aircraft and helicopters, and halting his troops about 120 miles outside of Moscow, Mr. Prigozhin left with an amnesty deal — and an enormous grin. Video of his withdrawal showed cheering throngs of well-wishers rushing his motorcade for selfies and handshakes.

If the terms of amnesty are to be believed, they are generous: the thousands of Wagner fighters who charged north under arms to Moscow were pardoned, with the Russian defense ministry to take command of Wagner fighters elsewhere.

According to the terms of the deal, Mr. Prigozhin himself is granted safety in Belarus, the Russian satrap that shares a border with both Russia and Ukraine. Since Wagner’s orderly retreat from Rostov and the outskirts of Moscow, Mr. Prigozhin has neither seen nor heard, with his press apparatus mostly silent on details about their leader.

Yet Russian press indicate that the deal President Putin struck with Mr. Prigozhin is unraveling. It may have been disingenuous from the outset. Kommersant, a Russian daily newspaper, reports that Mr. Prigozhin’s “rebellion” is still under investigation by an unspecified department in Russia’s Federal Security Service, the FSB.

A source in Russia’s General Prosecutor’s Office told a domestic news agency, RIA Novosti, that the criminal case against Mr. Prigozhin “has not been terminated.” Mr. Lukashenko is Europe’s longest-serving head of state, largely thanks to the support he has received from Russia following the 2020 presidential election he claimed to have swept.

The election was widely seen as fraudulent by outside observers, and Mr. Lukashenko violently crushed the subsequent domestic unrest that erupted following the election. Belarusian constitutional changes in 2022 provided the legal framework for stationing Russian nuclear weapons in Belarus — a story the Sun broke just before Russia invaded Ukraine last February — cementing Minsk in Moscow’s orbit.

Negotiating a truce is a feather in Mr. Lukashenko’s cap — but the strongman has tried to play the dictator-turned-peacemaker statesman on several occasions.

In 2014 and 2015, he unsuccessfully attempted to broker a deal between Russia and Ukraine, and again shortly after the Russo-Ukrainian War erupted last year. This time, Lukashenko was more successful.

One Belarusian news agency, Belta, reported that Mr. Lukashenko “held negotiations with Wagner’s boss Yevgeny Prigozhin with approval of the Russian president” in negotiations that “lasted for the entire day.”

Yet since Mr. Putin’s fiery tirade — a speech in which the Russian president mentioned neither Wagner nor its leader by name but vowed to crush the insurrectionists — new news has emerged concerning Mr. Prigozhin. Notably, other top Russian brass — including Mr. Putin — have not made recent appearances either. 

Russia’s defense minister, Sergei Shoigu, did appear in a video released today in which he met with military commanders and appeared to discuss the war in Ukraine. Russian military bloggers cast doubt on the video’s timeline and suggested the video was recorded before Mr. Prigozhin’s march toward Moscow but released today.

Mr. Putin also made a brief appearance in a video released by the Kremlin, but like Mr. Shoigu’s video, it may have been footage from a previous event, rebroadcast today. Given Mr. Putin’s displeasure at Mr. Prigozhin, and Belarus’ subservient status to Russia, the risk to Mr. Prigozhin of capture, kidnapping, or assassination is not to be discounted.

Mr. Prigozhin’s phoenix-like ability to navigate political crises and outmaneuver enemies is remarkable. How he manages to weather an investigation by the FSB may prove to be the most challenging act of his career and one in which his life hangs in the balance.