Insurance companies are among plaintiffs trying to stop accountancy firm Arthur Andersen selling off Enron's assets, according to court papers.

They want the accountants to disclose any assets it disposes of as they try to recover their investments in the failed energy trader.

American National Insurance and other firms filed an injunction last month to prevent Andersen selling or transferring assets outside the US.

American National's attorney Andrew Mytelka said: "We're one of the claimants that has lost significant dollars in securities."

Meanwhile, dozens of investors who together lost billions of pounds in the Texas-based company are being represented in a class action lawsuit. This accuses Enron bosses, accountants and banks of fraudulent involvement in its collapse.

The allegations centre on the use of off-balance sheet partnerships that effectively hid Enron's debt.

Banks that helped construct the partnerships are among the defendants.

Insurance broker Aon and insurer GE Capital were involved in at least one Enron partnership. The precise nature of the deals is not known.