Three people, including an Arvada Police Department officer, have died after a shooting in Olde Town on Monday afternoon, police said.

Arvada Deputy Chief Ed Brady said a gunman fatally shot the male officer before being shot and killed himself. A bystander was also taken to a hospital and pronounced dead.

“At this time, we believe this person was shot and killed by the gunman,” Brady said.

The officer was later identified as Gordon Beesley, a 19-year department veteran. The other two deceased have not been identified. Details about the shooter’s death have not been released.

Brady said the incident began at 1:15 p.m. when officers responded to the Olde Town Arvada Square, near the library, on reports of a “suspicious incident.” Around 15 minutes later, the department received multiple 911 calls reporting that an officer had been shot.

The Arvada Police Department issued a shelter-in-place order and secured the area of West 57th Avenue and Olde Wadsworth Boulevard for several hours, with many visitors taking shelter in local businesses as police cleared the scene.

There is no ongoing threat to the public and police are not looking for any other suspects, Brady said. However, police originally said there were two suspects.

All shelter in place orders have been lifted.

The identities of the deceased will be released after their families have been notified, Brady said. Officials have not yet determined the identity of the bystander.

This is only the third time an Arvada police officer has died on duty in the department’s history, according to Arvada Mayor Marc Williams. This is the first on-duty officer death that has involved a firearm.

“This is by far the saddest day for our police department,” Williams said.

Arvada closed its City Hall and canceled a City Council meeting Monday to provide resources to investigators and other first responders.

In a statement released Monday evening, Gov. Jared Polis said officials were “closely monitoring the troubling situation in Arvada.”

“My thoughts are with the family and friends of the officer who was tragically killed in the line of duty while swiftly and bravely responding to protect civilians in the area,” Polis said.

This incident comes three months after a gunman opened fire and killed 10 people, including a police officer, at a supermarket in Boulder, about 20 miles northwest of Arvada. Arvada police helped respond and investigate that attack.

Olde Town Arvada is the city’s downtown district with an array of shops, restaurants, breweries and other businesses.

It’s listed on the National Register of Historic Places and is about 7 miles northwest of downtown Denver.

“We are all beyond saddened and stunned by the events that unfolded in Olde Town Arvada today,” said Joe Hengstler, director of the Olde Town Arvada Business Improvement District.

“We thank our many businesses that took swift and careful action to keep patrons and passers-by as safe as possible. … Arvada is a resilient city and will endure in the days and weeks ahead.”

The Arvada Police Department held a procession for Beesley on Monday evening, with dozens of police vehicles driving behind a hearse carrying his body to the Jefferson County coroner’s office.

Numerous residents lined the street with flags to watch the procession, including John Garrod of Arvada, who held a black and white flag with blue stripes at the beginning the line.

Garrod said he hangs the flag outside his house whenever an officer is killed. His son, brother-in-law and nephew are all in law enforcement, he said.

“It breaks my heart whenever this happens but especially when it happens so close to home,” Garrod said. “These are the same officers I wave to when I am walking my dog.”

Those who wish to support the Beesley’s family should direct all donations to cofallenhero.org, the police department said.

The Associated Press contributed to this report.