Prince William, Prince Harry and Duchess Kate gathered to pay their respects to the victims of the London attacks

LONDON, ENGLAND - APRIL 05: The Very Reverend Dr John Hall, Dean of Westminster speaks with Prince William, Duke of Cambridge, Catherine, Duchess of Cambridge and Prince Harry during the Service of Hope at Westminster Abbey on April 5,2017 in London, United Kingdom. The multi-faith Service of Hope was held for the four people killed when Khalid Masood committed an act of terror in Westminster on Wednesday March 22. Survivors, bereaved families and members of the emergency services joined The Duke and Duchess of Cambridge, Prince Harry, the Home Secretary, Amber Rudd and London Mayor, Sadiq Khan, in the congregation. (Photo by Dan Kitwood/Getty Images)

It was a somber day for the royal family in London today.

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On Wednesday, Prince William, Prince Harry and Duchess Kate attended a multi-faith service to mourn the four innocent lives lost during a tragic recent terrorist attack in London.

On March 22, five people were killed and 20 were injured after a vehicle drove through a crowd of people at Westminster in London. After crashing into a gate, the attacker got out of the vehicle and fatally stabbed a police officer. The assailant was among the five killed in the attacks.

The royals laid a wreath at the scene with a handwritten message that read, “For PC Keith Palmer, and all those who have served our community so valiantly. Your legacy is our way of life. William,” according to E! News.

Photo by Dan Kitwood/Getty Images

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Over 400 faith leaders and first responders attended the service along with 200 diplomatic representatives from across the world. Each member of the congregation was given a candle upon their arrival at Westminster Abby. The service began at noon and was broadcast across the U.K..

One day after the attack, the Duchess spoke about mental health and shared her sympathies for the victims.

“Before I begin, I know you would all want to join me in sending our thoughts and prayers to all those sadly affected by yesterday’s terrible attack in Westminster,” she said. “We will be thinking of all the families, as we discuss the important issues we’re here to talk about.”

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