A small private airplane mistakenly entered restricted airspace near President Joe Biden's Delaware vacation home Saturday, prompting the brief evacuation of the president and first lady, the White House and the Secret Service said.

The White House said there was no threat to Biden or his family and that precautionary measures were taken. After the situation was assessed, Biden and his wife, Jill, returned to their Rehoboth Beach home.

The Secret Service said in a statement that the plane was immediately escorted from the restricted airspace after “mistakenly entering a secured area.” The agency said it would interview the pilot who, according to a preliminary investigation, was not on the proper radio channel and was not following published flight guidance.

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As is standard practice for presidential trips outside Washington, the Federal Aviation Administration published flight restrictions earlier this week before Biden’s beach town visit. The restrictions include a 10-mile radius no-fly zone contained with a 30-mile restricted zone.

A CBS News reporter said on Twitter that he saw Biden motorcading to a Rehoboth Beach fire station. The group of reporters that travels with the president was not part of the motorcade.

Federal regulations require pilots to check for flight restrictions along their route before taking off. Still, accidental airspace breaches, particularly around temporary restricted zones, are common.

U.S. military jets and Coast Guard helicopters are often used to intercept any planes that violate the flight restrictions around the president. Intercepted planes are diverted to a nearby airfield where aircrews are interviewed by law enforcement and face potential criminal or civil penalties.