Law enforcement officers sweep the parking lot at the site of a shooting at a King Soopers grocery store in Boulder, Colorado, US March 22, 2021. [Photo/Agencies] Multiple people were killed, including a police officer, in a shooting on Monday at a supermarket in Boulder, Colorado, and a suspect injured in the incident was arrested, authorities told a news conference hours later. Police said they had few immediate details of the shooting and no known motive for the violence, which unfolded at about 3 pm at a King Soopers grocery store in the Table Mesa area of Boulder, a city at the eastern foot of the Rockies about 28 miles (45 km) northwest of Denver. Commander Kerry Yamaguchi of the Boulder Police Department told reporters that investigators were just starting to process the crime scene and that he did not know precisely how many people died in the shooting. "We had multiple people who were killed in this incident, and I'm sorry to have to report that one of them was a Boulder police officer," Yamaguchi said. Boulder County District Attorney Michael Dougherty said the number of dead was known to law enforcement and would be made public later. Yamaguchi said the person taken into custody was believed to be the only individual with injuries who survived the bloodshed. He gave no details about the suspect. Yamaguchi also said that a second incident reported by police at an apartment building 3 miles (5 km) away as being possibly connected to the supermarket shooting turned out to be unrelated. The Boulder Police Department said earlier on Twitter that there is an "active Shooter at the King Soopers on Table Mesa" and urged local residents to "avoid the area". Live video from local TV stations showed a large police presence outside the supermarket. TV footage showed people were escorted out of the supermarket by police officers. A shirtless man with blood on his leg was taken out of the supermarket in handcuffs by three police officers, live TV footage showed. A law enforcement source told ABC News that officers responded to a report of someone shot in the parking area, and when they arrived at the scene, a suspect opened fire on them. Further information about the incident was not immediately provided by local authorities. Two witnesses told The Denver Post that they saw a gunman entering the store. "He didn't say shit," one of the witnesses was quoted as saying by the newspaper. "He just came in and started shooting." The other witness told The Denver Post that the gunman "let off a couple of shots, then was silent, and then he let off a couple more. He wasn't spraying". "Like my fellow Coloradans, I am closely watching unfolding events at King Soopers in Boulder," tweeted Colorado Governor Jared Polis. "My prayers are with our fellow Coloradans in this time of sadness and grief as we learn more about the extent of the tragedy," he noted.