A husband and wife who prosecutors alleged were interested in supporting the Islamic State have been found guilty of preparing an act of terrorism, the Guardian reports. Mohammed Rehman, 25, intended to detonate a suicide bomb either at a shopping center in London or on the Underground.

In May, under the display name “Silent Bomber,” Rehman, 25, asked his Twitter followers to help him pick a target. “Westfield shopping centre or London Underground? Any advice would be appreciated greatly,” he tweeted. The attack would be timed, prosecutors said, to commemorate the 10th anniversary of the London bombings of July 7, 2005 that left 52 people dead

According to the Associated Press, Rehman and his wife Sana Ahmed Khan, 24, lived in Reading, about 40 miles west of London. Prosecutor Tony Badenoch said they had a “common interest” in extremist ideology. Khan allegedly helped Rehman pay for chemical bomb-ingredients on eBay.

The couple’s marriage, it turned out, was secret: Rehman was divorced, and Khan’s parents did not approve of him. Both lived with their families. From the Guardian:

They had a keen interest in Islamic State and Rehman’s online research showed he “wished to play his own part”. One online post used a profile picture of Jihadi John.

The same day, he trawled YouTube for details about the London bombings and the “martyrdom” video of Shehzad Tanweer, one of the 7/7 bombers whom he referred to as his “beloved predecessor”. Rehman also told a Twitter user: “Why don’t you head to the London Underground on the 7th July if you got the balls.”

The undercover investigator engaged Rehman in a private conversation in which the defendant subsequently asked him “how dumb these Kuffar [non-Muslims] are lol”.

Rehman told the officer that he was preparing to die. He also asked whether the officer would like to join him, or whether he would go the “lone wolf route.” According to the Guardian, Rehman even broadcast his intentions on Twitter: “Now I just make explosives in preparation for kuffar lol and when I’ve made the required amount I’ll be wearing them on my chest.”

The jury deliberated for three days before finding the couple guilty of planning a terrorist act. Rehman was also convicted of possessing an article to be used for terrorist purposes. They will be sentenced later this week, the AP reports.

Image via Thames Valley Police/AP. Contact the author of this post: brendan.oconnor@gawker.com.