Gunman kills 10 people in a supermarket in the United States

Colorado, United States: At least 10 people have been killed, including a police officer, in a shooting at a supermarket in the U.S. city of Boulder, Colorado, less than a week after eight people were shot dead in the U.S. city of Atlanta.

Police arrested a suspect but did not disclose his name or details of the shooting at a news conference that evening.

Investigators have just begun sorting out evidence and witness interviews and did not have details on a motive for the shooting, Mr. Michael Dougherty, district attorney in Boulder County, said.

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"This is a tragedy and a nightmare for Boulder County, and in response to this, we have the cooperation and assistance of local, state and federal authorities," he added.

The shooting happened around 3pm local time (9pm GMT) at a King Soopers supermarket in the Table Mesa area of ​​Boulder, a town at the eastern foot of the Rockies, about 45 miles northwest of Denver.

Authorities said the suspect was receiving medical treatment and there was no further threat to the public.

Video footage of the scene, previously broadcast by television stations, shows a shirtless, bearded man in boxer shorts being handcuffed away from the store before being placed on a stretcher and loaded into an ambulance.

The man in custody apparently had a bloody leg and he limped as he walked.

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Boulder Police Department Commander Kerry Yamaguchi said police are still investigating and have no details on the motive for the violence.

Witnesses described scenes of pandemonium when they heard gunfire inside the supermarket.

"We were at the checkout, and shots were just starting to go off," said Sarah Moonshadow, 42, who was in the store with her son, Nicholas.

"And I said, 'Nicholas is getting off,' and Nicholas ducked away. And we just started listening and there, just repeated shots ... and I just said, 'Nicholas, run,' 'Moonshadow later told Reuters news agency.

Moonshadow says he "saw someone lying in the road" when she and her son fled.

'And I tried to run to him, and Nicholas pulled me away and said,' We have to go. "And we just ran behind the building and hid." The woman broke down in sobs and added: 'I could not help anyone