US official accused Russia of being behind a car bombing in rebel-held Ukraine that Russian media is using to fan war flames

• A US official accused Russia of being behind a car bombing in rebel-held eastern Ukraine.
• Russian media has been using the incident in Donetsk to fan the flames of war.

A US official accused Russia of being behind a car bombing in rebel-held eastern Ukraine that Russian media has been using to stoke concern that Ukrainian forces are targeting separatist leaders.

"Announcements like these are further attempts to obscure through lies and disinformation that Russia is the aggressor in this conflict," a US State Department spokesperson told reporters, according to ABC News reporter Conor Finnegan.

The spokesperson added: "This type of false flag operation is exactly what Secretary Blinken highlighted in his remarks to the UN Security Council."

A false flag is a secretive military operation that seeks to get an adversary, such as Ukraine, blamed for the actions by one's own operatives, a type of misdirection that Russia frequently employs in conflicts.

One Russian state-owned news service claimed the car blew up in a parking lot of a government building in Donetsk. The car belonged to the head of the Donetsk separatist police, Financial Times journalist Max Seddon reported.

On Russian state-owned television, an anchor asked on-air if war was on the horizon, according to multiple reports.

Ukraine's Defense Intelligence service also said on Friday that it believes Russian forces are planting explosives under various infrastructure in Donetsk, and urged residents to stay home.

"These measures are aimed at destabilizing the situation in the temporarily occupied territories of our state and creating grounds for accusing Ukraine of terrorist acts," it wrote in a statement.

The bombing occurred after Kremlin-backed separatist leaders in eastern Ukraine's Donbas region announced on Friday that civilians in the area will be evacuated to Russia.

It is "cynical and cruel to use human beings as pawns to distract the world from the fact that Russia is building up its forces in preparation for an attack," the State Department spokesperson said.

The leaders of the self-proclaimed Donetsk People's Republic and Luhansk People's Republic blamed Ukrainian aggression for the move, which Kyiv has denied.

"Allegations that the Ukrainian government intends to launch an offensive operation in Donbas are divorced from reality," Ukraine's foreign ministry spokesperson Oleg Nikolenko said in a statement.

Nikolenko added: "Ukraine is also NOT conducting or planning any sabotage acts in Donbas. We categorically reject attempts by Russia to aggravate already tense security situation."

Both the US and NATO have warned this week that Russia may try to create a pretext for an armed attack against Ukraine.

This story is developing. Please check back for updates.