Updated

Sen. Rand Paul's office says he was held by the Transportation Security Administration on Monday, although TSA officials deny characterization he was "detained" at Nashville Airport after an incident at the security gate.

Paul's father, presidential candidate Ron Paul, tweeted early Monday, "My son @SenRandPaul being detained by TSA for refusing full body pat-down after anomaly in body scanner in Nashville. More details coming."

Moira Bagley, the senator's spokeswoman, told Fox News that Paul (R-Ky.) called her after he went through a "full body screener," described to her as a body-imaging machine, and was stopped for an anomaly around his leg. The senator lifted his pants leg to show nothing was there and offered to go back through the machine, but the TSA official said no, only a full-body pat down would suffice.

Bagley said Paul refused, resisting on the grounds that it infringes on his rights and "private property."

Paul's office said that the TSA official told the senator to sit down in the security area and was not given an indication of when he would be allowed to leave. Security then escorted him out of that area, but let him remain in the airport. He missed his flight.

A law enforcement official said Paul was not detained, despite claims to contrary. According to TSA, Paul triggered an alarm during routine airport screening using "millimeter wave imaging technology," which creates a generic image to protect passenger privacy. When an alarm occurs a yellow box indicates where on the body to look for the anomaly. An individual is then patted down.

"When an irregularity is found during the TSA screening process, it must be resolved prior to allowing a passenger to proceed to the secure area of the airport. Passengers who refuse to complete the screening process cannot be granted access to the secure area in order to ensure the safety of others traveling," Greg Soule, TSA spokesman said in a statement.

Bagley said Paul was "not carrying a weapon." Since the incident, he has boarded a flight to arrive in Washington Monday afternoon.

Pat downs are an issue near and dear to Paul's heart. In a hearing before the Senate Homeland Security and Governmental Affairs Committee last year, Paul repeatedly asked TSA Administrator John Pistole about pat downs after a little girl was videotaped getting an invasive pat down.

Paul's father, who is a 12-term Texas congressman, has also called for defunding TSA. On Monday, his campaign issued a statement from Paul saying the actions against his son are an example of wasted federal spending.

"The police state in this country is growing out of control. One of the ultimate embodiments of this is the TSA that gropes and grabs our children, our seniors and our loved ones and neighbors with disabilities. The TSA does all of this while doing nothing to keep us safe," Paul said.

Fox News' Trish Turner and Mike Levine contributed to this report.