Vigils held in London and Cambridge for Saskia Jones and Jack Merritt, who died on Friday

Friends and family of Saskia Jones and Jack Merritt, the two people killed in Friday’s London Bridge attack, have attended memorials to honour them in London and Cambridge.

Boris Johnson, Jeremy Corbyn and the mayor of London, Sadiq Khan, stood alongside each other for a silent vigil in Guildhall Yard in central London on Monday before speeches by Khan and the Bishop of London.

After the minute’s silence, Khan said: “We come together this morning as Londoners to remember, to honour and to mourn the innocent lives lost as a result of this horrific terrorist attack on Friday. The best way to defeat this hatred is not by turning on one another but by focusing on the values that bind us.”

He called on Londoners to “draw inspiration from the lives of Jack and Saskia who, from a very early age, chose to dedicate themselves to helping others”.

Merritt, 25, and Jones, 23, were stabbed to death by the convicted terrorist Usman Khan, 28, on Friday. They both had a specialist interest in criminology and had been attending an event for Cambridge University’s Learning Together programme – which focuses on prisoner rehabilitation – when they were attacked.

As Khan spoke, there were sobs in the crowd from friends of the victims. Natasha and Marielle, two of Jones’s schoolfriends, had travelled with a group of others to lay flowers for her. She had attended Bloxham school near Banbury before going on to study criminology at Anglia Ruskin and then Cambridge University.

Facebook Twitter Pinterest Mourners attend a vigil at Guildhall Yard in central London. Photograph: Leon Neal/Getty Images

Natasha told the Guardian: “She was just so very kind. We want it to be remembered how kind she was and what a beautiful singer as well. We all sang in a choir together at school.

Marielle said: “I just hope that this terrible situation doesn’t negate what they believed in. I hope people will think about the work they did.”

Pastors and church groups were present at the London event, offering support to those affected by the violence.

Eustace Constance, who leads a team of response pastors, said he expected people attending to be in need of support.

He said: “We attend any events where people are traumatised, from Grenfell to terror attacks. We know that trauma can affect people in many different ways, some people might just want to cry and let it all out and we are here for them. We’ve also created a remembrance tree inside the church here and anyone of any faith can go in and place a memory on that tree.”

Facebook Twitter Pinterest Sadiq Khan called on Londoners to ‘draw inspiration from the lives of Jack and Saskia’. Photograph: Henry Nicholls/Reuters

The ceremony was led by Sarah Mullally, the bishop of London. Mustafa Fields, the director of the multi-faith organisation Faith Forums for London, also spoke. He offered prayers for the victims and emergency services and “all the Muslims grieving at the attacks in the name of their faith”.

After the vigil, those present entered the Guildhall to sign a book of condolences to the victims.

In Cambridge, Leanne O’Brien, Merritt’s girlfriend, broke down in tears as she attended a vigil in his memory. She was with his family at a service and minute’s silence in Cambridge, where the city’s mayor, Gerri Bird, led tributes outside the Guildhall. O’Brien wept and clutched a cuddly toy as she was supported by family and friends at the event.

After the vigil, those present entered the Guildhall to sign a book of condolences to the victims.