Nine years before Usman Khan killed two people in a stabbing spree on London Bridge, he was overheard by British security services discussing how to use an al Qaeda manual he had memorised to build a pipe bomb.
It was a snippet of conversation, along with other intelligence about a plot to bomb the London Stock Exchange, that prompted British police to arrest Khan – then 19 years old – and a group of older men on Dec. 20, 2010.
Sentenced to a minimum of eight years in prison in 2012 with a requirement that the parole board assess his danger to the public before release, he was set free in December 2018 – without a parole board assessment.
On Friday, he strapped on a fake suicide vest, armed himself with large kitchen knives and went on the rampage at a conference on prisoner rehabilitation beside London Bridge.
Confronted by bystanders, including a Polish man brandishing a narwhal tusk he had grabbed from the wall of Fishmongers’ Hall, Khan was wrestled to the ground. Three armed police officers surrounded him. They fired twice. He was dead.
“This individual was known to authorities,” said Britain’s top counter terrorism officer, Assistant Police Commissioner Neil Basu. “A key line of enquiry now is to establish how he came to carry out this attack.”
It has yet to be confirmed why Khan, now 28, began his rampage on London Bridge. The ISIS said the attack was carried out by one of its fighters and was in response to its calls to target countries that have been part of a coalition fighting the terror group, according to its Amaq news agency. The group did not provide any evidence.
London Bridge was also the scene of another deadly attack before the 2017 election, but British authorities have cast doubt on those claims of responsibility made by IS.
Then, three terrorists drove a van into pedestrians before stabbing people in the surrounding area, killing eight and injuring at least 48.