White House officials think that Chief of Staff John Kelly’s personal cellphone was compromised at some point, according to Politico.
Politico on Thursday reported that three U.S. government officials say the breach potentially occurred as early as last December.
The discovery inspires fear that data on Kelly’s device was exposed to foreign governments or hackers while he was Homeland Security secretary or after he joined the West Wing.
The potential breach was detected earlier this summer when Kelly turned his phone in to White House tech support staff.
Officials said Kelly told the staffers the phone had not been updating software or working properly for months.
Some Twitter users on Friday expressed anxiety over the possibility that Kelly’s device was breached.
A White House official said that Kelly had not used the personal phone often since joining President Trump’s administration.
Politico’s source said Kelly instead relied on his government-issued phone for official communications.
The official did not dispute any reporting on the timeline of events or the existence of a one-page memo last month summarizing the incident to administration officials.
The source added that Kelly no longer has possession of the device before declining to say where it is now.
One of the U.S. government officials noted that Kelly is now using a different phone, though he relies on a government version when inside the White House.
One source also said that the September memo triggered concern in the White House about what information may have been exposed.
Several government officials added it is unclear when or where Kelly’s phone was first compromised, and what, if any, data was accessed.
Kelly joined Trump’s administration last January after the former Marine general retired in 2016 as chief of U.S. Southern Command.