By Elena Teslova
MOSCOW (AA) - Russia claimed on Monday that investigators working on the March 22 terrorist attack on the Crocus City concert hall in Moscow region obtained evidence about the involvement of Ukraine's intelligence in the affair.
The Investigative Committee said in a statement that the information allows to speak about Ukraine's involvement in preparation of the attack.
"Investigators have already received significant data on the circumstances of the preparation of terrorists for a crime, which may testify for their connection with the Ukrainian special services," it said.
The head of the committee, Aleksandr Bastrykin, ordered investigators to thoroughly study the causes and conditions of the crime, it said.
At least 144 people were killed and more than 550 others injured when gunmen opened fire at the concert venue in Krasnogorsk, Moscow Oblast. Russia has charged four people for being directly involved in the attack.