Herndon Town Hall unplugged its phone lines yesterday after listeners of a talk show on WMAL-AM flooded the switchboard with what officials said were hate calls against a proposed day-laborer site.

The phones began ringing nonstop about 9:30 a.m., officials said, just after a substitute host on "The Michael Graham Show" called the proposed gathering spot for immigrant workers a "day-care center for illegal criminal aliens" and urged listeners to complain to Herndon Mayor Michael L. O'Reilly.

"You need to help . . . Mayor O'Reilly understand he's advocating breaking the law . . . and assisting criminal aliens who are in this country destroying this country, stealing jobs, running drugs, raping people. This is not an approved activity for the mayor of Herndon, Virginia," host Mark Williams said, according to an audio recording on the station's Web site. Williams broadcast from KFBK-AM in Sacramento.

He then read aloud the telephone number of Town Hall dozens of times and urged listeners to "melt that switchboard" and picket O'Reilly's law office a block away.

"We didn't have any second thoughts about pulling the plug" on the Town Hall phones, said Town Manager Steve Owens, reached late yesterday on his personal line. "This was a tsunami." The volume of calls threatened to crash the phone system of the small building, he said, and the comments were offensive. "They were vile and resembled hate speech. . . . They were anti-immigrant," Owens said.

Williams, reached in California last night, said the callers were expressing an "anti-illegal immigrant sentiment," not an anti-immigrant sentiment.

Those who phoned Town Hall after the system was shut down were greeted all day and into last night by loud static and a recorded voice saying the call could not be completed.

Owens said he notified Herndon police that the mayor's law office might be picketed or defaced. But O'Reilly, reached as he headed to the Delaware shore for the weekend, said the threats did not materialize.

Williams was filling in for Graham, who was suspended without pay from the Washington station last week for describing Islam as a "terrorist organization" on his two-hour program.

The mayor said he was turning his radio dial on the AM spectrum to hear the news and stopped at WMAL when he heard a mention of day laborers as he pulled his car into his office parking lot. He returned from a court case an hour later and heard the last few minutes of the show.

"Day laborers are not from another planet," O'Reilly said last night. "They're people. If people feel their borders aren't secure, they need to be talking to Congress or the president. I have a border with Loudoun County, not South America." He accused Williams of trying to "promote his ratings and excite his audience."

The struggles of the four-square-mile town of 23,000 in northwest Fairfax County to absorb newcomers, many of them in the country illegally, have mushroomed into an emotional debate over immigration policy. The Town Council will vote this month on whether to formalize what has been an informal gathering place at a 7-Eleven parking lot, where about 150 laborers seeking work assemble most days.

The town's Planning Commission this week narrowly rejected a proposal from a local social service group to build a tax-supported site on the Loudoun border. But the vote was not binding, and the council often differs with the commission.

Leaders of the nonprofit Project Hope and Harmony said people outside Herndon are politicizing a local issue.

"The one thing that we have tried to keep at arm's length are those groups that want to come into our town with their agenda to incite some kind of controversy that goes far beyond the issue we're trying to solve," said Joel Mills, a member of the group's executive council.

Loudoun officials jumped into the debate this week, saying the proposed day-laborer site sits partly in their county. Zoning Administrator Melinda Artman said Project Hope and Harmony may need to seek a special exception permit from Loudoun because the property would be for commercial use in a residential neighborhood. Owens said Herndon is reviewing Loudoun's concerns.

Herndon Town Council member Ann V. Null, a guest on yesterday's radio show, has been vocal about her opposition to spending tax money to accommodate day laborers.

She said she wrote a letter to the station's general manager last night to express disappointment that Williams "was urging listeners to call Town Hall with the intent of sabotaging the phone lines."

"I do not approve of this at all, " Null said.