The BBC, ITN and Sky News have handed hundreds of hours of unbroadcast footage of the August riots to police after being served with court orders by Scotland Yard.

The broadcasters were forced to hand over raw footage of the riots after the Metropolitan police obtained a production order earlier this month under the Police and Criminal Evidence Act 1984. The Daily Telegraph is also understood to have disclosed material to the police after being served with a production order.

Scotland Yard has put sustained pressure on all media groups to reveal video and picture evidence of the riots since the disorder across England seven weeks ago.

"It is very very rare that we are served with a court order to hand over footage like this," said a senior insider at one of the broadcasters. "We don't hand over material willy-nilly because it compromises the security of our journalists on the streets. Clearly we don't want them being seen as an evidence-gathering arm of the police."

The major news broadcasters are in the process of handing over hundreds of hours of footage to the police. The BBC, ITN and Sky News were issued with a wide-ranging order that forced the disclosure of "any broadcast or unbroadcast video or still pictures of the recent unrest in London".

Police are understood to have temporarily halted attempts to obtain footage from newspapers, except the Daily Telegraph, which is understood to have complied with a court order in early September.

The Times and the Guardian have consistently challenged the police requests. It is understood that Independent News & Media, owner of the Independent, has not yet been contacted by police.

"Police requests for BBC untransmitted material are dealt through our legal department, regardless of the subject matter," said a spokeswoman for the BBC.

"We require requests for untransmitted material to be made through the courts. A production order requiring footage of the riots was served on the BBC and a court agreed that the material should be supplied."

In deciding whether to grant a production order, judges are supposed to weigh the interest of the police in obtaining evidence with the public interest in a free press.

An ITN spokesman said: "ITN's policy is that we do not release unbroadcast material to police. On some occasions when the police apply to a judge for a court order to force the release of such material, we have challenged the police's application."

Hundreds of police officers are working through about 40,000 hours of CCTV footage in stations across the country. In London, Met officers are believed to be studying more than 20,000 hours of video at 30 viewing facilities.

A spokeswoman for the Metropolitan police said: "The police are identifying people through pictures, CCTV and through the media to ensure that people are brought to justice. We would ask the media to work with the police to ensure that happens."

A Sky News spokeswoman said: "Our standard policy is that we do not supply material to the police without a court order. On occasions – as has happened with some of our footage of the riots – where police request untransmitted material and an order is obtained we will comply with it."

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