Bankrupt US energy firm Enron has fired Arthur Andersen as the company's auditor.
It comes after Arthur Andersen admitted its employees destroyed Enron documents.
The accounting firm faces federal investigations and allegations that it failed to report irregularities by Enron.
Enron chairman Mr Kenneth Lay said: "While we had been willing to give Andersen the benefit of the doubt until the completion of that investigation, we can't afford to wait any longer in light of recent events, including the reported destruction of documents by Andersen personnel and the disciplinary actions taken against several of Andersen's partners working in its Houston office."
Mr Lay said Enron would immediately begin the selection process for a new external auditor.
Andersen, which this week fired the partner who handled the Enron account, denied it was aware of any improprieties until it was informed of concerns about the company's books by Sherron Watkins, an Enron vice-president.
PA