Internal Revenue Service employees using thousands of computers accessed prohibited Web sites that included personal e-mail, sexually explicit sites and games. To Treasury investigators, it was a sign that "significant misuse" of the Internet continues after a crackdown a year ago.

"Employee abuse of the Internet is still widespread," the investigators reported.

The results of the Treasury Department investigation disappointed lawmakers who pushed the IRS to revise its Internet policies and block access to prohibited sites after a study in 2001 showed IRS employees spent more than half their workday on the Internet for personal reasons.

"This is a classic case of people getting an inch and taking a mile," Senate Finance Committee Chairman Charles Grassley said Thursday.

"Nobody should collect a government salary to sit on their behinds and play around in chat rooms," said Grassley, R-Iowa, who oversees the Treasury Department and Internal Revenue Service.

More than 28 percent of the inappropriate Web browsing was traced to 122 computers, leading investigators to conclude that a small number of employees were chronic abusers.

But the investigators found enough evidence that IRS employees accessed prohibited sites to determine that a large number of employees continue to use the Internet inappropriately. The study could not determine the exact number of employees involved.