The daughter of a Russian ultra-nationalist and ally of President Vladimir Putin who argued Russia should absorb Ukraine has been killed in a suspected car bomb attack.

Russian state investigators said Darya Dugina, daughter of idealogue Alexander Dugin, was killed after a suspected explosive device detonated on the Toyota Land Cruiser she was travelling in on Saturday evening.

State news agency TASS quoted Andrei Krasnov, who knew Ms Dugina, as saying the vehicle belonged to her father and he was probably the intended target.

Father and daughter had been attending a festival outside Moscow and Ms Dugin had decided to switch cars at the last minute, Russian government newspaper Rossiiskaya Gazeta reported.

Footage showed Mr Dugin at the scene after the explosion, his hands clutching his head in horror.

Other video showed investigators collecting debris and fragments from the site.

Investigators from the Moscow region who described Darya Dugina as a journalist and political expert said they had opened a murder case.

They said they would be carrying out forensic examinations to determine what had happened.

The investigators said they were considering “all versions” when it came to working out who was responsible for the crime.

Maria Zakharova, a spokeswoman for Russia’s foreign ministry, said that if the murder investigation’s trail led to Ukraine, then it would point to a policy of “state terrorism” being pursued by Kyiv.

But Mykhailo Podolyak, an adviser to Ukrainian President Volodymyr Zelenskyy, denied his country was involved in the killing, saying on national TV: “We are not a criminal state, unlike Russia, and definitely not a terrorist state.”

He appeared to blame internal power struggles between “various political factions” in Russia for the attack, and suggested the incident was the “Karmic” payback for supporters of Russia’s actions in Ukraine like Ms Dugina and her father.

Mr Dugin has long called for the unification of Russian-speaking and other territories in a vast new Russian empire.

He wants the empire to include Ukraine, where Russian forces are currently carrying out what President Putin calls a “special military operation” to demilitarise the country.

Some Russia watchers have asserted Mr Dugin’s influence over Mr Putin is significant, while others have argued it is minimal.

Mr Dugin is sanctioned by the US.

Ms Dugina, who also went by the surname Platonova and was reported by Russian state media to be 30 years old, broadly supported her father’s ideas.

She has appeared on state TV to offer support for Russia’s actions in Ukraine.