U.K. Prime Minister Boris Johnson reassured the public that "anybody involved" in Friday's terrorist attack on London Bridge "will be hunted down and will be brought to justice." A man imprisoned six years for terrorism offenses before his release last year stabbed several people in London on Friday, two fatally, before being tackled by members of the public and then fatally shot by officers on London Bridge. Neil Basu, London’s police counterterrorism head, said 28-year-old Usman Khan was attending a program that works to educate prisoners when he launched the attack, killing a man and a woman and injuring three others just yards from the site of a deadly 2017 van and knife rampage. Basu said the suspect appeared to be wearing a bomb vest but it turned out to be “a hoax explosive device.” Health officials said one of the injured was in critical but stable condition, one was stable and the third had less serious injuries. The attack raises difficult questions for Britain’s government and security services. Police said Khan was convicted in 2012 of terrorism offenses and released in December 2018 “on license,” which means he had to meet certain conditions or face recall to prison. Several British media outlets reported that he was wearing an electronic ankle bracelet. Prime Minister Boris Johnson said he had “long argued” that it was a “mistake to allow serious and violent criminals to come out of prison early.”