-- Two senior Wal-Mart executives knew cleaning contractors were hiring illegal immigrants, many of whom were housed in crowded conditions and sometimes slept in the backs of stores, according to a federal agency's affidavit.

The affidavit, unsealed last week, was part of an investigation by federal immigration officials that led to the 2003 raid on 60 Wal-Mart stores in 21 states. The retailer agreed to pay $11 million in March to settle the case. It has said that top executives neither knew of nor encouraged the practice, but that is contradicted by the newly released documents.

The affidavit was filed by the Bureau of Immigration and Customs Enforcement to secure search warrants for a 2003 raid on Wal-Mart Stores Inc. headquarters in Bentonville, Ark. It was unsealed Nov. 2 by a U.S. district judge in Fayetteville, Ark. at the request of James L. Linsey, a New York attorney representing more than 200 former employees in a lawsuit against Wal-Mart.

In the affidavit, investigators said testimony and taped conversations from 2003 showed two executives at Wal-Mart headquarters knew that contractors cleaning its stores in several states employed illegal immigrants.

Wal-Mart denied there was any incriminating evidence in the affidavit and said the comments by executives that it contained were "bits and pieces of information from larger conversations."