The U.S. House of Representatives Ethics Committee started an investigation on Thursday into a sex scandal involving a Republican congressman who resigned last week.

Mark Foley (File Photo)

The committee approved about four dozen subpoenas for witnesses and documents for the investigation, which was launched over an unfolding scandal over sexually suggestive messages sent by former Republican lawmaker Mark Foley to young, male congressional pages.

Foley, 52, resigned last Friday after disclosure he sent sexually explicit e-mails.

Earlier this week, the Justice Department ordered House officials to preserve all records related to Foley's electronic correspondence with teenagers.

House Speaker Dennis Hastert, who had been criticized for his handling of early warnings about the Foley's behavior, said he would cooperate but refused to resign.

"The bottom line is I am taking responsibility for it because ultimately the buck stops here," Hastert said at a news conference in his district of Batavia, Illinois.

"I'm sorry that this happened. We are now trying to correct the problem," he said.

At the White House, spokesman White Snow said President George W. Bush and Vice President Dick Cheney supported Hastert and did not want him to resign.

In the Congress's page program, young people work for lawmakers in exchange for insights into the U.S. political system and are referred to as "pages."

VietNamNet/Xinhuanet