MINSK, Belarus — Russian mercenary leader Yevgeny Prigozhin is at St. Petersburg while his Wagner troops have remained at the camps where they had stayed before a short-lived mutiny against Moscow, the president of Belarus said Thursday.

Belarus’ president, Alexander Lukashenko, helped broker a deal for Mr. Prigozhin to end his rebellion on June 24 in exchange for amnesty and security guarantees for himself and his soldiers and permission to move to Belarus.

However, few details of the agreement have emerged, and the whereabouts and futures of the Wagner company’s chief and his private army have remained unclear. The Kremlin has refused to comment on Mr. Prigozhin’s location or movements since the abortive revolt.

After saying last week that Mr. Prigozhin was in Belarus, Mr. Lukashenko told international reporters Thursday that the mercenary leader was at St. Petersburg and Wagner’s troops still were at their camps.

He did not specify the location of the camps, but Mr. Prigozhin’s mercenaries fought alongside Russian forces in eastern Ukraine before their revolt.

Mr. Lukashenko said his government offered Wagner, a private military contractor founded by Mr. Prigozhin, the use of Belarusian military camps but the company had not made a final decision.

Asked if Mr. Prigozhin and his mercenaries were going to move to Belarus, Mr. Lukashenko answered evasively that it would depend on the decisions of the Wagner chief and the Russian government. 

The Belarusian leader said he doesn’t think Wagner’s presence in Belarus could lead to the destabilization of his country.

During their short revolt, they quickly swept over the southern Russian city of Rostov-on-Don and captured military headquarters there before marching on the Russian capital. 

Mr. Prigozhin described it as a “march of justice” to oust the Russian defense minister and the General Staff chief.

Mr. Prigozhin claimed his troops had come within about 125 miles of Moscow when he ordered them to stop the advance under the deal brokered by Mr. Lukashenko.

The abortive rebellion represented the biggest threat to President Putin in his more than two decades in power and exposed the Kremlin’s weakness, eroding Mr. Putin’s authority.

The Wagner fighters faced little resistance, smashing occasional roadblocks and downing at least six helicopters and a command post aircraft, killing at least 10 airmen.

Mr. Lukashenko’s statement followed Russian media reports saying Mr. Prigozhin was spotted at St. Petersburg, Russia’s second-largest city. His presence was seen as part of agreements that allowed him to finalize his affairs there.

Russian media outlets claimed Mr. Prigozhin retrieved cash that was confiscated during raids of his offices and a small arsenal of weapons he kept at his home in St. Petersburg.

Russian online newspaper Fontanka posted videos and photos of Mr. Prigozhin’s opulent mansion and some personal items, including a collection of wigs of various colors. 

It also published a collection of selfies that showed him posing in various wigs and foreign uniforms, an apparent reflection of Wagner’s deployments to Syria and several African countries.

Mr. Lukashenko said he warned Mr. Prigozhin that he and his troops would be destroyed if they failed to make a deal to end their mutiny and that Belarus would send a brigade to help protect Moscow.

He argued that the rebellion could lead to major bloodshed and plunge Russia into a civil war.

“It was necessary to nip it in the bud. It was very dangerous, as history shows,” Mr. Lukashenko said.