The Russian government has blamed the attack at a Moscow concert hall on hefty financial support from Ukraine.
This was disclosed by an investigative committee on Thursday.
Last week, the attack at a Moscow concert hall left more than 140 people dead.
A group of terrorists, who Russian President Vladimir Putin described as being radical Islamist, stormed a large music venue just outside of Moscow.
They went on a gun rampage, killing people on sight as they went towards the main hall, and set it on fire.
Russian officials had claimed that the terrorist attack at the Crocus City Hall may have been organised by Ukrainian special services who used the Islamists as proxies.
The committee said: “Confirmed information [indicated] that perpetrators of the terrorist act had received significant sums of money and cryptocurrency from Ukraine, which were used in the preparation of the crime.”
Since the incident, the death toll from the attack had reached 140, Russian Health Minister, Mikhail Murashko said.
According to him, people seriously hurt in the terrorist attack eventually died from their injuries.