Russian investigators have detained a woman in their hunt for the killers of pro-war blogger Vladlen Tatarsky in a blast at a St Petersburg cafe.
In video released by authorities - most likely recorded under duress - Darya Trepova is heard admitting she handed over a statuette that later blew up.
But in the footage, she does not say she knew there would be an explosion, nor does she admit any further role.
Investigators said they had evidence the attack was organised from Ukraine.
However, Kyiv officials said it was a case of Russian infighting.
More than 30 people were wounded in the bombing in Russia's second city.
Tatarsky had been attending a patriotic meeting with supporters in the cafe as a guest speaker late on Sunday afternoon.
A video circulating on social media showed a young woman in a brown coat apparently entering the cafe with a cardboard box.
Images showed the box being placed on a table in the cafe before the woman sat down. Another video showed a statue being handed to Tatarsky.
In a brief excerpt of her interrogation released by the ministry, Darya Trepova, 26, appeared under duress as she sighed repeatedly.
When her interrogator asked if she knew why she was detained, she replied: "I would say for being at the scene of Vladlen Tatarsky's murder... I brought the statuette there which blew up."