AlphaBay was a marketplace on the Darkweb until it was taken down by the FBI on 4 July 2017. The Darkweb is a part of the access which can only be accessed by using special browsers.
When counter-terrorist detectives raided Mohammed Humza's house in Watford, on the outskirts of London, they found a MacBook computer which he had used to log onto the Darkweb, a court heard on Thursday, 8 October.
Prosecutor Benjamin Holt said Humza, 29, had used the username mh.nn243 to log into the AlphaBay marketplace and agree deals to buy F1 fragmentation grenades and Semtex explosives.
He was arrested in November 2016 when it turned out the person mh.nn243 was trying to buy them from was actually an undercover FBI agent.
Humza, who not in court, has denied attempting to possess explosive substances for unlawful purposes between July and September 2016.
Mr Holt pointed out the username contained the initials of Humza and his wife, Nazir Naz.
But Humza, who answered no comment during police interviews, claims he was not the only person to have access to the mh.nn243 username.
On Thursday, 8 October, Anders Ho, a National Crime Agency officer gave evidence at the trial at the Old Bailey.
Mr Ho, who works for the NCA's Darkweb Intelligence and Exploitation Unit, said he had carried out several test purchases on AlphaBay before it was closed down by the US authorities in 2017.
He explained that the only way two people could user the same AlphaBay username was if they both knew…
