The King has visited Golders Green to show his support for the area's Jewish community after the stabbing attack last month.
There were cries of "long live the King" and one man told Charles he was "always welcome" in the area.
The King told him "it's a dangerous world isn't it?" and responded, "I know" when the member of the public said: "What happened in Golders Green was horrific".
Charles told others further down the long line of people waiting to see him: "I hope I haven't disrupted your normal activities too much."
The visit follows an incident on 29 April when two Jewish men were stabbed in Highfield Avenue.
The men, aged 34 and 76, were treated at the scene for stab wounds, with both being taken to hospital.
After the attack, the UK terror threat level was raised to severe - meaning an attack is likely within the next six months. It is the first time it has been raised this high since 2021.
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During the King's visit, dozens of smiling people, many of them Jewish, gathered to shake his hand and thank him for coming.
Children could be seen among the well-wishers, beaming after having had the chance to see the monarch.
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King Charles visited a Jewish Care charity centre on Thursday to meet with victims Shloime Rand, 34, and Moshe Ben Baila, 76, also known as Norman Shine, along with Chief Rabbi Sir Ephraim Mirvis and Metropolitan Police Commissioner Sir Mark Rowley.
He also spoke with members of the Jewish community police force Shomrim, who were involved in responding to the attacks on 29 April.
After speaking to the King, Mr Shine, who was stabbed in the neck outside a bus stop during the attack, spoke about the "genuine warmth" he had felt from the King.
"The most inspiring thing was that he didn't let go of my hand, I mean it was amazing, he is the King but I felt a genuine warmth and concern."
"We feel we have a genuine friend in the King," he added.
(c) Sky News 2026: King visits Golders Green to show solidarity with Jewish community
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