Ukraine's Zelenskyy sacks top officials as Russia warns of 'doomsday'

Ukrainian President Volodymyr Zelenskyy has fired the head of the country's security service (the SBU) and its prosecutor general, citing hundreds of criminal proceedings into treason and collaboration by people within their departments.

"Today, I made the decision of relieving of their duties the prosecutor general and the head of Ukraine's security service," Zelenskyy said in his daily address to the nation on Sunday.

He said over 650 cases of suspected treason and aiding and abetting Russia by Ukrainian security officials are currently being investigated.

"In particular, more than 60 employees of the prosecutor’s office and the SBU have remained in the occupied territory and work against our state,” Zelenskyy said.

"Such an array of crimes against the foundations of the state’s national security, and the links recorded between Ukrainian security forces and Russian special services raise very serious questions about their respective leaders," he said.

Dismissed Prosecutor General Iryna Venediktova has been replaced with her deputy Oleksiy Symonenko. 

Ivan Bakanov, sacked head of the SBU, was a long-time friend of Zelenskyy, according to Ukrainian news agencies.

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Moscow warns of doomsday

Meanwhile, Dmitry Medvedev, the deputy head of Russia's Security Council chaired by President Vladimir Putin, responded to Ukrainian officials' statements that Kiev may strike the bridge linking Crimea and Russia, warning that that would trigger devastating consequences for the Ukrainian leadership.

"If that happens, the consequences will be obvious: They will momentarily face Doomsday," Medvedev said on Sunday. "It would be very hard for them to hide."

Medvedev, who once was touted by the West as more liberal compared to Putin, said Russia will press its action in Ukraine until fulfilling its stated goal of "denazifying" and "demilitarising" the country. 

He predicted that the continuing fighting will "undoubtedly lead to the collapse of the existing regime" in Kiev.

Kiev has accused Moscow of launching fresh strikes on multiple residential areas in eastern and southern Ukraine.

The fresh strikes came after Moscow announced that it would step up its military operations and Kiev accused Russia of installing missile launchers at Europe's largest nuclear plant.

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