A Russian newspaper says a senior general with the country's military has been arrested in connection to the rebellion carried out by the Wagner Group.

Sergei Surovikin is the deputy commander of Russia's military operations in Ukraine. The Moscow Times cited sources close to the defense ministry in its report Wednesday.

It said Surovikin reportedly chose to side with Wagner leader Yevgeny Prigozhin during the uprising. The two are said to have been close.

There have been questions around Surovikin's whereabouts since the mutiny. One Russian journalist said on social media Surovikin had not been in contact with his family for three days.

Meanwhile, the New York Times reported Surovikin knew about Prigozhin's plans in advance.

Kremlin officials denied the report, chalking it up to speculation.

NHK spoke to a former US ambassador to Russia about how mercenaries were able to advance without much resistance, hinting they could have had help.

Former US Ambassador John Sullivan said, "That's difficult to understand if there was no support for Prigozhin within the Russian military and security services."

Sullivan also commented on the possibility President Vladimir Putin may lose power.

"It's somewhat more likely now than a week ago, just because this mutiny by Prigozhin has revealed actual weakness in President Putin. So it could happen but I'm not predicting it," he said.