Elements inside the Ukraine government gave the go ahead for a car bomb attack that killed a prominent Russian female figure in August, US intelligence agencies believe, according to a report Wednesday.
The attack near Moscow killed Daria Daria Dugina, the daughter of a prominent Russian nationalist.
The New York Times reported that US officials fear an element of a covert campaign was involved in the attack, which they warn could widen the ongoing conflict.
The US was not part of the attack and had not provided intelligence or other assistance, according to officials who spoke to the newspaper.
US officials said they were not aware of the operation, according to the report, adding that American officials would have opposed the killing had they been consulted.
The US was informed about the role of Ukrainians last week, said the Times.
The US is concerned that such attacks could affect the course on the battlefield and provoke Russia to conduct strikes against senior Ukrainian officials, it said.
"American officials have been frustrated with Ukraine's lack of transparency about its military and covert plans, especially on Russian soil," said the report.
It also said the actual target, Dugina's father, Aleksandr Dugin, was believed by the operatives to be with his daughter in the vehicle. The elder Dugin has maintained a hawkish attitude toward Ukraine, said the Times.
It remains unknown which elements of the Ukrainian government ordered the attack or whether President Volodymyr Zelenskyy, signed off on the operation.
Russian authorities blamed Ukraine for organizing the attack and in late August Dugin called for revenge against Ukraine in his first remarks with the Times after the operation.