Hillary Clinton campaign also hacked in attacks on Democrats

The computer network used by Democratic presidential candidate Hillary Clinton's campaign was hacked as part of a broad cyber attack on Democratic political organizations, people familiar with the matter told Reuters.

The latest attack, which was disclosed to Reuters on Friday, follows reports of two other hacks on the Democratic National Committee and the party's fundraising committee for candidates for the U.S. House of Representatives.

The U.S. Department of Justice national security division is investigating whether cyber hacking attacks on Democratic political organizations threatened U.S. security, sources familiar with the matter said on Friday.

Campaign officials were involved in crisis talks after the public disclosure of the Justice Department investigation.

Hours after the disclosure, it issued a statement claiming its own cyber security review had found 'no evidence' of a breach.

Spokesman Nick Merrill said: 'An analytics data program maintained by the DNC, and used by our campaign and a number of other entities, was accessed as part of the DNC hack.

'Our campaign computer system has been under review by outside cyber security experts. To date, they have found no evidence that our internal systems have been compromised.'

But in an astonishing twist, Yahoo News reported that the campaign had been warned by the FBI it was at risk in March - but refused to turn over details to federal investigators to help them catch the perpetrators.

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