At least three people were killed and several injured after a gunman opened fire at a packed mall in the capital Copenhagen. Among the injured, three are said to be in critical condition.

Police Inspector Soren Thomassen told reporters that a 22-year-old Danish man was arrested over Sunday’s shooting and charged with manslaughter. He said there was no indication that anyone else was involved in the attack, and said that it was too early to speculate on a motive for the shooting. He also said that the suspect had a history of psychiatric issues, he said, but he did not elaborate.

A 47-year-old man and a boy and girl, both 17, were killed in the shooting, according to law enforcement.

Four other people were shot, including two Danish women, 19 and 40 years old, and two Swedish citizens, a man, 50, and a girl, 16. The four were in “serious condition” at a hospital, Thomassen said. Copenhagen police later said that 20 people sustained minor injuries during the chaos that followed the shooting and that “three more were treated for possible stray shots” before being taken home.

The attack rocked Denmark at the end of an otherwise joyful week, just after it hosted the first three stages of the Tour de France cycle race. The event had sent hundreds of thousands of cheering Danes into the streets across the country.

“Denmark was hit by a cruel attack on Sunday night. Several were killed. Even more, wounded. Innocent families shopping or eating out. Children, adolescents, and adults,” Prime Minister Mette Frederiksen said in a statement late on Sunday.

“Our beautiful and usually so safe capital was changed in a split second,” she said. “I want to encourage the Danes to stand together and support each other in this difficult time.”

The shooting happened in the late afternoon at Field’s, one of the biggest shopping malls in Scandinavia and located on the outskirts of the Danish capital.