A minute’s silence has taken place at Radio 1’s Big Weekend in Hull in honour of those killed and injured in the Manchester attack.
Fans marked the moment at 3pm with the music stopping on all three stages, followed by cheering for the city.
Katy Perry is headlining the festival at Burton Constable Hall in East Yorkshire.
Radio 1 Breakfast Show presenter Nick Grimshaw said Big Weekend was a “community of music lovers”.
He added that everyone had been thinking about Manchester all week feeling “completely heartbroken”.
This is the moment 25,000 people fell silent.
Security has been ramped up at transport hubs around Hull and at entrances to the festival site.
Radio 1 controller Ben Cooper says every bag will be searched and every person checked twice across the weekend.
“What happened in Manchester has absolutely been at the forefront of our minds in making sure that we are utterly determined to provide a safe and secure environment for people to enjoy themselves,” he told Newsbeat.
There are armed police, sniffer dogs and airport-style scanners at entry points to the site.
Image caption There is a highly visible police presence around the grounds of Burton Constable Hall
The two-day event will also see performances from Stormzy, Little Mix, Kasabian, Kings of Leon and Bastille.
“I don’t have any concerns because of the experts that we’ve been consulting with,” he said.
“They are the best in the country and the most informed in the country.”
He added that the extra support will allow “50,000 people will come together and show that they are not afraid”.
Zara Larsson was first up on the main stage on Saturday and paid tribute to Manchester.
“Music unites us all,” she told fans.
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