Jeff Gillooly, Ms Harding's former husband, may plead guilty to masterminding the plot today and is expected to say that she was involved.
Mr Gillooly is said by his brother John to have implicated Ms Harding after being confronted with a statement by her implicating him. The Oregonian newspaper said yesterday that he had expected her to stick with their original story, denying they were behind the assault.
Mr Gillooly is believed to have agreed to a plea-bargain with prosecutors under which he will plead guilty and be sentenced to two years in prison and fined dollars 100,000 ( pounds 67,000). On Friday, NBC reported that he had repeatedly told the FBI that Ms Harding knew about the plot to maim her rival.
The new witness is a hotel clerk who was working at the Westin hotel in Detroit and who says that on 6 January - the day Ms Kerrigan was struck on the leg - he received a telephone call from Ms Harding asking for Ms Kerrigan's room number. The authorities in Portland, Oregon, where Ms Harding lives, believe she gave the room number to Mr Gillooly, who at this stage wanted to make the attack in the hotel.
Even if the police cannot prove that Ms Harding conspired to make the attack, they may arrest her for aiding a cover-up. 'The cover- up would be easier to establish,' said an official. 'There is no smoking gun here.' In either case, the chances of Ms Harding staying in the US Olympic figure-skating team are looking slim.
'Miss Harding should assume responsibility for her actions and take herself out of the competition,' the Washington Post said yesterday in an editorial. But a Los Angeles Times editorial carried the headline 'Innocent until proved guilty, Harding should skate'.
In an effort to keep her place in the team. Ms Harding admitted on Thursday - and asked forgiveness for - knowing details of the assault after it had occurred and failing to pass this information on to the authorities. She may even have lied about what she knew when first questioned by the police on 18 January, changing her story when they said they knew that she was lying.
Although the skater's arrest in Portland was reported to be 'a virtual certainty' earlier in the week, the police are having difficulty in finding evidence of her involvement from witnesses other than co-conspirators. Under Oregon law, some corroborative evidence is needed other than from those involved in the plot.
As investigations continue, no television news is complete without pictures of Ms Harding at practice on the ice in Portland where 2,000 people assemble every morning to watch her train. Michelle Kwan, 13, is expected to be sent to Norway as a possible replacement for Ms Harding if the US Figure Skating Association decides to change the team.
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