- Video report by ITV News Correspondent Richard Pallot
Tributes are being paid to a Cambridge University graduate named as Jack Merritt who was killed in the London Bridge terror attack.
It comes as so-called Islamic State made a unverified claim it is responsible for the attack, which caused the deaths of two people.
Mr Merritt was a course co-ordinator for the Learning Together programme which was hosting a conference at Fishmongers' Hall attended by Usman Khan.
He had originally read Law at Manchester University before going to Cambridge to further his education.
He celebrated his 25th birthday just last month.
Tributes have flooded in for the graduate, who has been described as "the best guy" in one social media post.
People who knew him posted on social media about his "open heartedness, his drive and his faith in the redemption of prisoners through education shone out. He saved lives through his work."
Others talked about how he was "widely loved, passionate about helping others and strongly concerned about youth justice, education & equal opportunity".
One woman was also killed in the attack, however her identity is not yet known.
Three people were also injured and taken to two London hospitals for treatment.
The condition of a victim who was critically injured has improved, NHS chief executive Simon Stevens said.
"While three people remain in hospital, this means two are now stable and a third has less serious injuries," he added.
The Metropolitan Police said it is awaiting information from the Coroner of the identity of the victims. It offered its ""heartfelt thoughts and condolences to all those families, both deceased and who still remain in hospital".
It added it had "no evidence to suggest anybody else was involved in this attack".
The force said it has received almost 500 videos and photos of the incident to date.
On Saturday evening, so-called Islamic State said it was behind the attack, although ITV News has not been able to independently verify this claims.
The Amaaq news agency, which acts as a mouthpiece for the terror group, posted a message on Telegram which translates as: "The person who carried out the attack in London yesterday is a fighter of the Islamic state. He carried out the attack in response to calls to attack the citizens of the nations of the allied forces."
Usman Khan, 28, has been named as the man behind the stabbing spree, which claimed the lives of two people.
He was a convicted terrorist release early on licence, having been put behind bars in 2012 for his role in a foiled plot to bomb the London Stock Exchange.
He has served just half of his 16-year sentence.
Giving a statement outside Scotland Yard, Metropolitan Police Assistant Commissioner Neil Basu said Khan was subject to an "extensive list of licence conditions" on his release from prison and that "to the best of my knowledge he was complying with those conditions".
It is understood that a Ministry of Justice review of the licence conditions of every terrorist offender has now begun.
Police are searching a property in the Midlands connected to Khan.