A former treasurer apparently stole at least $725,000 from the committee that runs House Republican campaigns, investigators for the group said Thursday.

An internal probe alleged that the former treasurer, Christopher Ward, used his authority to order wire transfers to siphon money meant for the National Republican Campaign Committee and other GOP groups into his own accounts. The funds were taken between 2001 and 2007, according to investigators.

Ward also appears to have taken at least $28,000 from the committee in charge of Senate Republican campaigns, said lawyer Robert K. Kelner, one of a team of lawyers hired by NRCC to investigate.

Ronald Machen, Ward's lawyer, said they had no comment on the investigation's findings.

Kelner detailed a scheme whereby Ward, 39, allegedly used his position at the committee to filter money to himself, either directly or through various other GOP committees. He submitted five years' worth of false financial audits for the NRCC, keeping others in the dark about his activities, Kelner said.

Despite the scope of the fraud, however, the investigators believe Ward acted alone.

A trusted hand who had been at the committee for a dozen years, he exploited his broad powers — including the ability to wire money through major banks without anyone else's authorization — rather than concocting an elaborate ruse to mask his misdeeds, investigators said.

"He doesn't appear to have undertaken a particularly clever fraud. This isn't a case where you have somebody who was being really thoughtful about covering his tracks or cloaking what he did," said Kelner, whose team spent more than four months investigating.

The case has been referred to the FBI, whose probe is ongoing.

The details on the extent of the NRCC's losses emerged at a punishing time for the GOP campaign committees, which are lagging badly behind Democrats in fundraising and facing a darkening political outlook.

On top of the losses it suffered because of the alleged embezzlement, the NRCC has shelled out some $530,000 for the investigation, and another $300,000-plus to beef up its accounting operations — a key recommendation of its lawyers.

"We got dealt a bad hand. We handled it as well as we could," said Rep. Tom Cole, R-Okla., the NRCC chairman.

The NRCC losses amount to less than GOP officials initially feared. Kelner emphasized, though, that the full scope of Ward's fraud could be larger. Investigators didn't have access to his bank records or detailed documentation on some of the accounts to which Ward had high-level access.

Ward's activities came to light in late January after he aroused the suspicion of top NRCC officials by repeatedly making excuses to avoid showing audit information to an oversight panel or arranging a meeting with auditors. He ultimately admitted that there had been no audit, and the NRCC ended its relationship with him, alerting the FBI.

Although Ward left his post as treasurer last summer, he stayed on as a consultant and continued to enjoy high-level access to NRCC accounts — including his wire transfer authority — through the end of 2007. Kelner said his last fraudulent transaction was in October.