Anthony Guglielmi, a Secret Service spokesperson, said the security-team member faces an internal investigation and potential criminal inquiry over allegations involving compromised “operational and information security.”

“While we will not comment on the specifics of this matter, one principle is unequivocal: any conduct that potentially threatens the safety of a protectee will not be tolerated,” Guglielmi said in a statement.

The agency did not identify the person under investigation.

The Secret Service said the investigation is tied to a report from MS NOW last week saying that some Secret Service agents had privately expressed frustration over last-minute travel requests from Vance and his family.

Vance’s office referred questions to the Secret Service.

Vance and his wife, Usha, live in the vice president’s residence at the U.S. Naval Observatory along with their young children.

On Sunday, the couple welcomed their fourth child, Alec Neel Vance, the first baby born to a sitting vice president in more than 150 years. He’s joined by older siblings Ewan, 9; Vivek, 6; and Mirabel, 4.