A gunman opened fire inside a busy shopping mall in the Danish capital on Sunday, killing several people and wounding several others.
A 22-year-old Danish man was arrested, Copenhagen police said, adding there was no indication that anyone else was involved in the attack, though they were still investigating.
Gun violence is relatively rare in Denmark and police said it was too early to speculate on the motive for the shooting.
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The shooting happened in the late afternoon at Field’s, one of the biggest shopping malls in Scandinavia, located on the outskirts of the Danish capital.
When the shots rang out, some people hid in shops while others fled in a panicked stampede, witnesses said.
“It is pure terror. This is awful," said Hans Christian Stoltz, a 53-year-old IT consultant.
Stoltz was bringing his daughters to see former One Direction band member Harry Styles perform at a concert scheduled for Sunday night near the mall.
Organisers called off the concert, which had been scheduled at the nearby Royal Arena, by order of police.
On Snapchat, Styles wrote: "My team and I pray for everyone involved in the Copenhagen shopping mall shooting. I am shocked. Love H.”
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Police gave no specific casualty count beyond saying several people were dead and several wounded.
They described the suspect was an “ethnic Dane”, a phrase typically used to mean someone is white.