Obama’s campaign organisers called the breach of security an “outrageous” invasion of privacy and demanded a full probe.

Bill Burton, a spokesman for Obama’s campaign, slammed the Republican government for using the information for “political purposes”.

“These unauthorised accesses were detected by the State Department and they were immediately acted upon,” said undersecretary Pat Kennedy. The incidents took place at separate times in January, February and March.

“The unauthorised access was caught by a monitoring system. When the monitoring system is tripped, we immediately seek an explanation for the record access,” Kennedy said. 

Spokesman Sean McCormack said the department’s initial take was that it was a matter of “imprudent curiosity”, and that an investigation had been launched into what was done with the information accessed.

“That is our initial take on the matter,” McCormack said. He declined to say whether the information had made its way out of the State Department. “We are not being dismissive of any other possibility,” he added.

Ex-rival backs Obama

Former White House hopeful Bill Richardson, a one-time member of the Clinton administration, on Friday said he was endorsing Senator Barack Obama for the Democratic presidential nomination.

“After careful and thoughtful deliberation, I have made a decision to endorse Barack Obama for president,” he said. Richardson said Obama would be “a historic and a great president, who can bring us the change we so desperately need by bringing us together as a nation here at home and with our allies abroad.”

“We are blessed to have two great American leaders and great Democrats running for president. My affection and admiration for Hillary Clinton and President Bill Clinton will never waver,” Richardson explained. He dropped out of the race for the Democratic nomination on January 10 after a poor showing in the first state-based primary and caucus contests.

‘Bad’ defence budget

The ever increasing US defence budget due to the war in Iraq has brought the current economic woes in the country, according to Obama. “How much longer are we going to ask our families and our communities to bear the cost of this war?” Obama asked at a rally in West Virginia on Friday. The US economy, which is being dragged down by an increasing budget deficit, rising oil price and a serious subprime crisis, has overtaken the war in Iraq as the top concern for American voters.