Bankrupt retailer Kmart Corp has suspended severance payments to several former executives as part of an investigation into the way the company was run under former chief executive officer Chuck Conaway.

The investigation is part of an accounting probe started in January and focuses on what the company called the "stewardship" of Kmart by members of its former management team. Concern was raised after an anonymous letter, claiming to be from employees, was sent to Kmart voicing concerns about accounting irregularities and other issues.

Further details of the accounting investigation will be included in Kmart's 10K annual financial statement filing, scheduled for release on May 15.

The retailer would not identify the individuals under scrutiny.

A number of top Kmart executives, including former CEO Conaway and president Mark Schwartz were ousted earlier this year. James Adamson, who had served on the Kmart's board, replaced Conaway, and is spearheading the company's restructuring in bankruptcy.

Kmart filed for Chapter 11 bankruptcy protection on 22 January. The company's operating results for the year ended 30 January are expected to include a loss "significantly higher" than the $244 million loss reported for the previous fiscal year.