It followed presidential security breaches that included a fence-jumper bursting into the White House on Sept. 19 and an armed ex-convict riding in an elevator with Obama in Atlanta a few days before that. Julia Pierson resigned Oct. 1 as director of the Secret Service amid pressure from members of Congress who had lost faith in her ability to protect the president.

The unidentified man said he was Representative Donald Payne Jr., a Democrat from New Jersey, the official said. One member of the White House staff determined that the man wasn’t Payne, and another asked him to leave, the official said. He did so without incident and wasn’t detained.

The Secret Service did its job by screening everyone who attended the dinner, including the man, said Brian Leary, an agency spokesman.

“This guy went through security, fully screened,” he said.