Prosecutors say Munir Mohammed, an asylum-seeker from Sudan, and London pharmacist Rowaida El-Hassan met on SingleMuslim.com and bonded over their shared extremist views.
Both defendants denied the charges, but jurors at London’s Central Criminal Court found them guilty of preparing terrorist acts.
Prosecutors said Mohammed volunteered to carry out an attack during Facebook exchanges with a man he believed to be an Islamic State group commander.
Police said they found bomb-making instructions and two of the three components for the explosive TATP at Mohammed’s home when he was arrested in December 2016.
Prosecutors say Mohammed drew on El-Hassan’s knowledge of chemicals during his preparations.
She acknowledged an “emotional attachment” to Mohammed, but denied plotting an attack.
Judge Michael Topolski said Mohammed, 36, had been “planning an explosion to kill and maim innocent people in the cause of Islamic State.” The judge said El-Hassan, 33, was “ideologically motivated to provide him with support, motivation and assistance.”
They are set to be sentenced Feb. 22 and face a maximum sentence of life in prison.