The singer, 32, performed on Thursday at an intimate show for only 90 people inside London’s Water Rats club, the same venue where she made her U.K. debut 10 years ago.
Katy Kats from around the world also had “the best seat in the house” thanks to Perry, who live-streamed the concert on YouTube.
“This week has been really hard. It sucked. It was hard for you guys and it was hard for me because we all love music,” she said as she held back tears. “We all listen to the same music, and you think about it, and think that’s my friend, that’s my sister, that’s my brother, that’s my cousin, that’s the person that loves music.”
Adding, “It’s awful, and whatever you can do to help, you should. And if you can’t do anything that’s fine, but what you should do is not let them win. I’m going to sing this next song for them. They can never take that part from us ever. Ever. Can we have a moment of silence before we start? Let’s do this.”
“I can’t really tell anyone else how they should feel, but I just feel devastated. The U.K., they are just so passionate about music—just like anyone else, but they are just so in it, and so dedicated and so loyal,” she said.
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Twenty-two people died, many of them teens and children, and around 75 were injured in the attack at Manchester Arena.
The deadly explosion occurred around 10:33 p.m. local time near the ticket office outside Manchester Arena, Greater Manchester Police Chief Constable Ian Hopkins said. Investigators suspect the attack was carried out by Salman Abedi, 22, who detonated an improvised explosive device and died at the scene, Hopkins said.
According to the SITE Intelligence Group, which monitors militant communication, ISIS has claimed responsibility for the attack.