• Formal complaint to Russian authorities after ‘co-ordinated attack’ on team working on story about dead soldier • Cameraman treated for concussion and other injuries

The BBC has made a formal complaint to Russian authorities after journalists from its Moscow bureau were attacked and had their camera equipment smashed.

The incident happened after Steve Rosenberg, the BBC’s Moscow correspondent, and a newsgathering team had interviewed the sister of a Russian soldier who had been told he was killed in military exercises “on the border with Ukraine”.

According to the BBC, the cameraman involved is continuing to receive treatment for concussion and other injuries.

A statement released by the BBC said: “After filming in the city of Astrakhan, our team was assaulted by unidentified men in a co-ordinated attack. Our staff were badly beaten, their camera destroyed and then taken. After alerting the emergency services, the team was then taken to a police station for four hours of questioning after which they discovered that recording equipment – which was in their vehicle, at the police station – had been electronically wiped.

“The attack on our staff, and the destruction of their equipment and recordings, were clearly part of a co-ordinated attempt to stop accredited news journalists reporting a legitimate news story.”

The statement added: “We deplore this act of violence against our journalists and call on the Russian authorities to conduct a thorough investigation and to condemn the assault on our staff.”

According to Rosenberg the team had their identities checked and the boot of their car examined while investigating “persistent reports of Russian servicemen being sent to fight in Ukraine”.

After the interview with the dead soldier’s sister the team went to a cafe in Astrakhan – a city in southern Russia close to the Caspian Sea.

Rosenberg, who filed a report on the attack for Radio 4’s Today programme on Thursday morning, said: “When we left the cafe and approached our vehicle, we were confronted and attacked by at least three aggressive individuals.

“Our cameraman was knocked to the ground and beaten. The attackers grabbed the BBC camera, smashed it on the road and took it away in their getaway car. We spent more than four hours at the police station being questioned by investigators.”

Rosenberg added: “On the way to the airport we discovered that, while we had been at the police station, some of the recording equipment in the car had been tampered with. The hard drive of our main computer and several memory cards had been wiped clean. Fortunately we had uploaded the interview to London earlier in the day. But why would anyone set out to destroy our material and to silence the sister of a Russian soldier?”

According to Interfax, the head of the Astrakhan region interior ministry’s press office, Petr Rusanov, said “a criminal case” had been launched following reports of an attack on a cameraman who had been “beaten and robbed by unidentified persons”.

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