The leader of Wagner, Yevgeny Prigozhinplanned to arrest two of Russia’s top military officials when he launched the mutiny on Saturday, the Wall Street Journal reported Wednesday, citing Western officials.

Prigozhin planned the arrest of the defense minister Sergei Shoigu and the supreme general Valery Gerasimov when the two visited an area along the border with Ukraine, CNN reports citing a WSJ report.

Russia’s Federal Security Service (FSB) learned of the plan two days before it was scheduled to take place, forcing Prigozhin to change his plans at the last minute and begin the march to Moscow, according to the report. Wagner’s mercenaries took control of a key military base in the city of Rostov-on-Don, and their troops approached the Russian capital when Prigozhin called off his mutiny.

When asked about the WSJ report, two European security sources told CNN that while it was possible Prigozhin had expressed a desire to arrest Russian military leaders, there was no assessment of whether he had a credible plan to do so.