Rumors have been circulating for hours that Valery Gerasimov, the chief of the Russian army's General Staff, has been killed in a missile strike on the Crimean peninsula.
According to preliminary information, Ukraine fired at least 10 Cruise Storm Shadow missiles on Thursday, hitting a command center in Crimea and killing at least 25 people, 10 of them special forces and five senior Russian military officials.
A large string of ambulances was seen at the scene, while the pro-Putin governor of Sevastopol called it "the worst and biggest attack of recent times.""
While Gerasimov has not been seen in public since December 29, rumours have circulated that he was killed in the rocket attack.
Ukrainian media have reported the rumors, and The Commander of the Air Force in Kiev, Lieutenant General Mykola Oleshchuk reportedly praised the "perfect combat work" of his forces.
However, Ukraine has made no claim that 68-year-old Gerasimov, who is also Putin's first deputy defence minister, had been injured or killed.
Nataliya Humenyuk, a spokeswoman for the Ukrainian Southern Defense Forces, said.
"We are collecting information that you are currently interested in. Once it has the right confirmation, it will be made public. "At the moment, we can only say what is already known – the command point has been hit," she said.
Rumors of Gerasimov's death appear to have begun to circulate after a Russian Telegram channel called "Ordinary Tsarism" posted an unconfirmed report.
It said: "According to preliminary data, Valery Gerasimov, who was at a command post near Sevastopol at the time of the attack, was killed in the attack in Crimea."
The message then disappeared, while no evidence was given of the authenticity of this announcement. The Kremlin has not yet commented on the speculation.