A Canadian woman killed in the latest London attack died in her fiance's arms after being struck by a speeding van as terrorists again brought havoc to the capital.

Christine Archibald, 30, would have had "no understanding of the callous cruelty that caused her death", her family said as they paid tribute to her.

She is the first named victim of the atrocity in London Bridge and Borough Market on Saturday night, which killed seven people and critically injured 21 others.

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Cassie Ferguson Rowe said her brother, Tyler Ferguson, held Ms Archibald, from British Columbia, and she died in his arms.

Writing on Facebook, she said: "Last night in London my baby brother lost the love of his life on the London Bridge. 

"In a split second his entire life was ripped away from him. Hearing his painful sobs on the phone while he's alone trying to deal with this tears me apart. 

"I have no words. If you know Tyler, please be there for him now, and later when what happened sinks in, he's going to need us all."

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Ms Archibald's family said in a statement: "We grieve the loss of our beautiful, loving daughter and sister. She had room in her heart for everyone and believed strongly that every person was to be valued and respected.

"She lived this belief, working in a shelter for the homeless until she moved to Europe to be with her fiance.

"She would have had no understanding of the callous cruelty that caused her death.

"Please honour her by making your community a better place. Volunteer your time and labour or donate to a homeless shelter. Tell them Chrissy sent you."

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Canadian Prime Minister Justin Trudeau said he was "heartbroken" to learn of Ms Archibald's death.

Applauding the UK for its strength and resilience in the face of adversity, he said: "These hateful acts do not deter us; they only strengthen our resolve.

"Canadians stand united with the British people. We will continue to work together with the United Kingdom and all our allies to fight terrorism and bring perpetrators to justice."

On Sunday, Prime Minister Theresa May visited some of the 48 people taken to hospitals across the capital after the attack.