Enron paid its team of 144 senior managers $744m in cash and stock in the year leading up to its bankruptcy, the scandal-ridden firm has revealed.

That is average pay of more than $5m for each executive.

Kenneth Lay, the firm's former chairman, is estimated to have received more than $150m, including his salary, bonus and stock options.

The news has infuriated former workers and shareholders who accuse the managers of raiding Enron's coffers at their expense.

The bonuses stand in stark contrast to the severance pay of up to $13,500 received by less senior Enron employees.

Improper retention?

Enron filed for bankruptcy in December after admitting it had vastly overstated its accounts for the previous five years.

It is one of the biggest corporate scandals to shake the US, and has had widespread ramifications for other firms who are rushing to clean up their accountancy practices.

In addition to the executive pay and awards, Enron paid $50m to retain 76 employees it deemed critical to its operations.

The retention bonuses came just three months before Enron's collapse, and were described as "a staple in bankruptcy planning" by the cash-short firm.

But some legal experts have said they were improperly paid and represented an unusually large amount of money.

Insider trading accusations

Enron's bankruptcy has spawned dozens of investigations and a slew of lawsuits from angry investors who saw their savings become worthless.

Enron's auditor, Andersen, has already been found guilty of obstructing justice by shredding evidence relating to Enron's accounts.

Enron has not yet faced a criminal charge, but is expected to do so.

One potential issue is insider trading, as senior executives have been accused of selling their share options while having access to exclusive information regarding Enron's predicament.

Among the other executives who shared in the pay were former chief executive Jeffrey Skilling and former chief financial officer Andrew Fastow.

Spokesmen from Mr Skilling, Mr Fastow and Mr Lay have not commented on the pay revelations.

The figures were disclosed in a 1,436-page filing with the federal bankruptcy court in New York.