US authorities are investigating reports that CIA Director John Brennan's personal email account has been hacked by a student.
The alleged hacker claimed in a statement to the New York Post that he had located files related to his work, such as an application by Mr. Brennan for a top security clearance.
The CIA said investigations are ongoing, but did not confirm whether the breach actually occurred.
The teenager who carried out the attack remains anonymous.
As described by the New York Post, the student in question is angry with American foreign policy.
On his Twitter , he had posted links to files, which he claims include Mr. Brennan's contact list, a list of phone calls from a former CIA director and other documents.
There was also a tweet with a list of names – including one claiming to be John Brennan – along with phone numbers, email addresses and Social Security numbers.
A statement from the CIA said: "We are aware of reports that have emerged regarding this incident on social media and have referred the matter to the appropriate authorities."
The alleged hacker also claimed to have compromised an email account belonging to Homeland Security Secretary Jeh Johnson.
The use of private emails by senior US officials has become a major issue in recent months, as it increasingly threatens the security of high-profile organizations, let alone those related to classified documents and national security matters.
