A US Senate Committee has joined other Congressional panels in an investigation of failed energy giant Enron.

The Governmental Affairs Committee's permanent subcommittee on investigations, said its panel will subpoena top executives and directors of Enron to determine their role in the collapse of the company. Additionally, financial and trading records from Enron and audit documents from its accountant, Arthur Andersen LLP, will be subpoenaed, according to Sen. Carl M. Levin (D-Mich.), Chairman of the Committee.

Enron's business practices had the mark of "a massive shell game with multiple layers of conflict of interest," said Sen. Levin.

Sen. Joseph Lieberman, D-Conn., the full committee's chairman, promised Wednesday "a search for the truth, not a witch hunt." He did not rule out an examination of Enron's relationships with the Bush administration.

The Senate Governmental Affairs Committee is among a half dozen committees and subcommittees expected to hold hearings in both the House and Senate in the coming months on Enron's collapse. The Securities and Exchange Commission and the Labor Department also have investigations under way.

Enron's attorney Robert Bennett claims the corporation is cooperating fully with investigations, having turned over more than 30 boxes of documents to the House Energy and Commerce Committee so far. Expressing his frustration at the ongoing investigations, Mr. Bennett said, "I don't question the legitimacy of an inquiry, but it's not a measured approach to have half a dozen different committees doing this at the same time."

In the middle of the growing firestorm about Enron, Andersen announced a clean peer review this week. The Public Oversight Board, an accounting industry oversight group, plans to look at the adequacy of the peer review system in light of the failed Enron audits.