Nov. 30 (UPI) -- The Islamic State on Saturday claimed responsibility for a deadly attack that killed two on London Bridge via its Amaq news agency.
The terror group -- also identified as Daesh, ISIS and ISIL -- did not provide any evidence for its assertion that suspect Usman Khan, 28, of Staffordshire, was one of its fighters. Police say they have so far found no evidence that anyone else was involved in the attack.
Khan served time in prison for a 2012 conviction for terrorism offenses, London police said Saturday.
Metropolitan Police Assistant Commissioner Neil Basu said in a statement Friday that Khan began the attack during a conference the University of Cambridge organized inside Fishmongers' Hall near the bridge's north end.
The first victim of the attack has been named as Jack Merritt, 25, who worked as the course coordinator for Learning Together, a criminology program for the University of Cambridge. He had been attending a conference at Fishmongers' Hall next to London Bridge and was described as a "champion for underdogs everywhere."
Police believe the attacker attended the Learning Together conference and that the attack began inside the building, before he left the building and was confronted and shot by officers.
Jack Merritt's father, David Merritt, wrote on Facebook that his son, an advocate for prisoner rehabilitation, "would not wish his death to be used as the pretext for more draconian sentences or for detaining people unnecessarily."
After his 2012 conviction in a plot to blow up the London Stock Exchange and other sites, Khan was initially sentenced to 16 years in prison, but was released early "on license," meaning he had to meet certain conditions or risk re-imprisonment. Authorities say he was not referred to the British Parole Board.
Police have been investigating how Khan carried out the attack even though he was known to authorities and fitted with an electronic tag to monitor his movements.
"It is very important that we get out of that habit and that we enforce the appropriate sentences for dangerous criminals, especially for terrorists, that I think the public will want to see," he said.
In addition to the two deaths, three others, a man and two women, were injured and hospitalized.
"While we are still in the early stages of the investigation, at this time we are not actively seeking anyone else in relation to the attack," Basu said in a statement early Saturday. "However, we continue to make fast time inquiries to ensure that no other people were involved in this attack and that there is no outstanding threat to the public."
Footage captured bystanders wrestling with a person lying on the ground before armed police pulled them to safety upon arrival on the scene.
In footage that has emerged since, one man is seen with a fire extinguisher that sprayed Khan while another man is seen with a narwhal whale tusk, pulled from the wall of Fishmongers' Hall, lunging at him, to pin down the attacker.