The evidence against would-be London bomber and his ex-wife wasn't particularly difficult to find. The pair stockpiled explosives in their London home, and set up a Twitter account to ask for advice on which targets to bomb, The Guardian reports.
Rahman's handle on Twitter, according to Sky News: @InService2Godd. And his Twitter name? "Silent Bomber." He didn't encrypt his tweets, so there were no obvious barriers for the intelligence community to find them. Twitter subsequently suspended the account.
On Tuesday, Mohammed Rehman and Sana Ahmed Khan were found guilty by the Old Bailey Court, and sentenced to life imprisonment for plotting an attack in London to mark the 10th anniversary of the 2005 bombings.
This latest threat raises some interesting questions about the balance between civil liberties and national security. As ArsTechnica points out, the tweets were not encrypted and were posted (not very well or secretively) by one man. Are plots like these enough to warrant laws that might pull back privacy rights for all citizens?
U.K. law enforcement's requests for account information from Twitter appear to be ramping up. In its transparency report, Twitter said 299 requests were filed in the first half of 2015. That's a jump from 116 requests in the latter half of 2014.
Social media companies have been grappling with similar questions of how to balance free speech and security for years.
On Tuesday, Twitter revised its rules regarding hate speech on social media in response to criticism from the FBI and other groups that it is not doing enough to help thwart terrorism.
"You may not promote violence against or directly attack or threaten other people on the basis of race, ethnicity, national origin, sexual orientation, gender, gender identity, religious affiliation, age, disability or disease," the revised rules stipulate.
But the company also stressed that it continues to "embrace and encourage diverse opinions and beliefs," while taking a hard line on those that cross the line.
Twitter said it doesn't comment on individual accounts and investigations.