WASHINGTON — New documents released by a Senate panel show how entrenched Washington Mutual was in fraudulent and risky lending, and highlighted how its top executives received rewards as their institution was hurtling toward disaster.

The problems at WaMu, whose collapse was the largest in American banking history, were well known to company executives, excerpts of e-mail messages and other internal documents show.

The documents were released on Monday by the Senate Permanent Subcommittee on Investigations, which began an inquiry into the financial crisis in November 2008. The panel has summoned seven former WaMu executives to testify at a hearing on Tuesday, including the former chief executive Kerry K. Killinger.

The panel called WaMu illustrative of problems in the origination, sale and securitization of high-risk mortgages by any number of financial institutions from 2004 to 2008.