The Belgian federal public prosecutor’s office said the suspect aimed to take down the Brussels Airport Company website and “infiltrate the computer system” on the night of 22 March 2016 but was unsuccessful.
Investigators traced the source of the hack to a property in Pittsburgh, Pennsylvania, and handed the information to US authorities.
“The FBI proceeded to conduct house search in Pittsburgh…and interrogated a minor of American nationality,” a spokesperson said. “He confessed.”
Preliminary interviews and searches of seized computers and other evidence have shown no indication of a “terrorist motive” or Isis links, prosecutors said.
“The Belgian federal public prosecutor’s office therefore wants to emphasise that this case has nothing whatsoever to do with that of the terrorist attacks on 22 March 2016 in Brussels,” a spokesperson added.
No further information was released on the suspect or his possible motivation.
The attempted cyber attack came just hours after two Isis suicide bombers blew themselves up in the departures hall of Brussels Airport, killing more than a dozen people.
The third intended bomber, Mohamed Abrini, survived and fled the scene, sparking an international manhunt before being arrested weeks later.
Little over an hour after the first explosions, another Isis militant detonated his explosives on a train at Maalbeek metro station, bringing the total death toll from the coordinated attacks to 35.
The jihadis behind the bombings were part of a wider cell that carried out the Paris attacks in November 2015, massacring 130 people in bombings and shootings at a concert hall, bars and the Stade de France.
Investigations into a wider network linked to the atrocities continue, with judges prolonging the detention of several suspects detained in connection with the Paris attacks on Thursday, as well as the alleged Brussels Jewish Museum shooter Mehdi Nemmouche and a man suspected of stabbing two police officers in Schaerbeek in October.
In a separate anti-terrorism investigation, 11 people were detained for questioning and then released after a series of house searches in Brussels overnight on Tuesday.
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