FBI agents raided the offices and homes of longtime Dallas County Commissioner John Wiley Price, his top aide and his political consultant Monday morning.

"All I can say is that I have no idea what is going on," Price said at a short mid-afternoon news conference at his attorney's office. "I came to my office this morning, and it had more people than usual in it."

Agents did not tell him anything about the purpose of the search, he said, adding that county business will proceed normally.

Price has been a high-profile political figure for nearly three decades and has become a lightning rod for criticism because of his occasional vocal outbursts during commissioner meetings.

He was first elected commissioner for District 3 in 1985 and has held the position ever since.

Beginning at about 10 a.m., a large number of agents began searching the first and second floors of the Dallas County Administration Building, the structure formerly known as the Texas School Book Depository.

"They're not letting anybody in, and they told the secretaries to leave," one county employee told NBC DFW of the raid.

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County Judge Clay Jenkins told The Associated Press that agents were executing a search pursuant to a federal warrant. Jenkins declined further comment, but said county commissioners would meet as scheduled Tuesday morning.

FBI spokesman Mark White said he could confirm that agents were at Price's office but declined to offer any details about why they were there.

Agents were also seen searching the residences of two of Price's aides, including executive assistant Dapheny Fain and political consultant Kathy Nealy. Agents also searched Nealy's car, which was parked in the administration building's parking lot.

The three work on Kwanzaafest, a yearly two-day festival at Fair Park celebrating black heritage. Price is founder of the event, Fain is president and Nealy is director, according to public tax records.

Mattie Thompson, who is secretary of Kwanzaafest, said she was not aware of any FBI investigation involving the event, and the FBI has not said the event is part of their investigation. Reached at her home in Irving, Thompson said she learned of the FBI raids on the news.

NBC DFW sponsored Kwanzaafest in the past two years but was not involved in any of its financing.

At his news conference, Price said this is not the first time in his political career that he has faced investigations.

Asked if it wasn't the first time FBI agents raided his office, he said it was the first time "for me to know."

Commissioner Maurine Dickey, an outspoken critic of Price, praised the FBI probe.

"I think it's a happy day for Dallas County," she said.

Dickey said the investigation was a long time in coming.

"If there is wrongdoing, they will do something about it," she said. "We're very fortunate to have an investigative agency such as the FBI that comes in and protects us all."

But Jenkins criticized her comments late Monday evening.

"I think any time you have something like this, it's a sad day," he said. "It's wrong to revel in something like this. It's wholly inappropriate. I'm disappointed that one of my commissioners said that."

The Commissioners Court has a regularly scheduled meeting at 9 a.m. Tuesday.

The FBI raids come six years after agents searched the office of then-Dallas Mayor Pro Tem Don Hill at City Hall. Hill and more than a dozen others were convicted in a bribery scheme involving public housing contracts.

NBC DFW's Ken Kalthoff, Susy Solis, Lindsay Wilcox, Frank Heinz and Ellen Goldberg, as well as The Associated Press, contributed to this report.