Vigils for the victims of the London Bridge attack have been held in London and Cambridge.

Jack Merritt, 25, and Saskia Jones, 23, were commemorated at the services, which included a minute’s silence.

They were stabbed to death by convicted terrorist Usman Khan, 28, at a prisoner rehabilitation conference on Friday.

The BBC has learned Khan was under investigation by MI5 when he left prison a year ago but given one of the lowest priorities.

Mr Merritt and Ms Jones were both graduates of the University of Cambridge’s institute of criminology and had been taking part in an event for its Learning Together programme – which focuses on education within the criminal justice system – when they were attacked.

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  • Mr Merritt’s family and his girlfriend attended the service in Cambridge outside the Guildhall.

    Prime Minister Boris Johnson and Labour leader Jeremy Corbyn were among those at the vigil at the Guildhall in the City of London.

    They were joined London Mayor Sadiq Khan who said the best way to defeat the hatred shown in the attack was to focus on the values of hope, unity and love.

  • “The best way to defeat this hatred is not by turning on one another, but it’s by focussing on the values that bind us, to take hope from the heroism of ordinary Londoners and our emergency services who ran towards danger, risking their lives to help people they didn’t even know,” he said.

    The London service happened less than a mile from Fishmongers’ Hall, where Usman Khan launched his attack on Friday.

  • Bishop of London Sarah Mullally said the vigils remembered “academics celebrating rehabilitation and finding only danger”.

    She paid tribute to the workers at Fishmongers’ Hall, who she said went to work to offer hospitality, but found themselves needing to give protection.

    A book of condolences is open at Guildhall Art Gallery and members of the public are invited to lay flowers outside nearby Mansion House.

  • The victims’ families paid tribute to their loved ones over the weekend.

    Mr Merritt was a co-ordinator of the Learning Together programme and Ms Jones a volunteer

    Ms Jones’s family said their daughter, from Stratford-upon-Avon in Warwickshire, had a “great passion” for supporting victims of criminal justice.

    In a statement, Mr Merritt’s family described him as a “talented boy” who “died doing what he loved”.

    Mr Merritt’s father went on to criticise the Daily Mail and Daily Express newspapers for their coverage of Prime Minister Boris Johnson’s promise to review licence conditions placed on convicted terrorists released from jail.

    On Twitter, David Merritt shared images of the Mail and Express front pages – which reported a “blitz on freed jihadis” – and wrote: “Don’t use my son’s death, and his and his colleague’s photos – to promote your vile propaganda. Jack stood against everything you stand for – hatred, division, ignorance.”

  • Cambridge University’s vice-chancellor Prof Stephen J Toope said he was “devastated to learn that among the victims were staff and alumni”.

    Toby Williamson, chief executive of Fishmongers’ Hall, praised the bravery of his staff who intervened to stop the attacker, hailing their actions as “extraordinary things done by ordinary people”.

    Mr Williamson told how Polish chef Lukasz suffered five wounds to his left-hand side as he fended off the knifeman with a narwhal tusk during “about a minute of one-on-one straight combat” – allowing others time to escape danger.

  • Two others grabbed makeshift weapons including a fire extinguisher before the attacker fled down a staircase and then got trapped in reception.

    Dr Vin Diwakar, medical director for the NHS in London, said two people injured in the attack remained in a stable condition in hospital, while one had been able to return home.