Three years ago, teenage England native Kane Gamble was able to access intelligence plans in Afghanistan and Iran by pretending to be the head of the CIA.

He’s now 18, and as of January 19 he is in custody in London for his crimes. He used a technique called “social engineering” to assume the identity of then head of the CIA John Brennan. He also targeted the US Secretary of Homeland Security and the US Director of National Intelligence.

Social engineering is when a person builds up a portfolio of information (pictures, personal details) and uses it to manipulate others into handing over even more information. This new information is then used to access the accounts of targets — in this case the US’s most powerful spy agencies.

“It involves manipulating people, invariably call center or help desk staff, into permitting acts or divulging confidential information,” the prosecuting attorney told The Telegraph.

The teenager persuaded call handlers at an internet giant that he was John Brennan, to gain access to his computers; he told an FBI helpdesk that he was Mark Giuliano, then the agency’s Deputy Director, to re-gain access to an intelligence database.

He would taunt his victims, release their personal info, and download pornography onto their computers. He pleaded guilty to 10 charges, and stated his reason for his actions was him “getting more and more annoyed about how corrupt and cold blooded the US Government” is.

According to the indictment, he committed a series of hacking-related crimes between June 2015 and February 2016. Gamble’s first target was Brennan, before he moved on to former US Secretary of Homeland Security Jeh Johnson.

Gamble was a part of a hacking group he founded in 2015, which according to The Guardian is known as “Crackas with Attitude.” Gamble’s online hacking alias is “Cracka”. The group regularly targets US officials in an effort to get the country to cut their ties with Israel, utilizing the #FreePalestine hashtag, according to The Guardian.

The information he stole about the intelligence operations was later posted on WikiLeaks.

His eight month reign of chaos was brought to an end in February 2016 after he gained access to the US Department of Justice’s network over a number of days, accessing details of 20,000 FBI employees and case files including that on the Deepwater Horizon Oil Spill, according to The Telegraph. He was then immediately arrested at his home in Leicestershire, England.

Details of his case have been kept secret until now due to him being a minor at the time of his arrest.

According to The Independent, the defense is utilizing the fact that Gamble has autism spectrum disorder in their argument against a sentence.