A stabbing attack at a crowded mall in Sydney, Australia, left six people dead and injured at least two others on Saturday afternoon. The rampage was the deadliest act of mass violence in the country since 2017.

The authorities said that the attacker, who has not been publicly identified, was shot and killed by a police officer. There was no longer a threat to the public, the police said.

Here’s what we know about the attack so far.

What happened in Sydney?

The attack happened at Westfield Bondi Junction, a popular shopping center in the Eastern Suburbs, an affluent area of Sydney near the coast.

Witnesses described a chaotic scene as shoppers noticed people running and saying that someone in the mall had a knife. As the attacker moved through the mall, the police said, he began to stab people.

Five people died of their injuries at the scene and one died later in a hospital, the police said. Among those hospitalized, some in a critical condition, was a 9-month-old baby.

Multiple calls were made from the mall about a stabbing, beginning shortly after 3:30 p.m. local time.

The attacker was shot and killed after a police officer was directed into the shopping center, where the man with the knife lunged at her with his weapon.

Michael Dunkley, 57, who witnessed the attack, said that the officer directed the man to drop the knife. The attacker “didn’t say anything,” Mr. Dunkley said. “He seemed determined.”

A motive for the attack is unclear.

The authorities have not formally identified the man but said they believed they know his identity, and that he was 40 years old and acted alone.

Police Commissioner Karen Webb of the New South Wales Police said the attacker’s motive was unclear, but there were no indications it was a hate crime or related to terrorism.

“If it is, in fact, the person that we believe it is, then we don’t have fears for that person holding an ideation — in other words, that it’s not a terrorism incident,” Commissioner Webb said.

One witness described the attacker as a thin man with a beard and short hair, who was wearing dark green pants and a green jersey.

Bondi Junction is a shopping and tourism hub.

Bondi Junction is a wealthy area of Sydney where tourists and beachgoers meander, shop and meet with friends.

The district draws crowds on weekends, where people can shop at high-end stores in the Westfield mall complex, see a movie or buy groceries.

During a major renovation in 2005, the area was known as one of the largest shopping centers in the Southern Hemisphere.

The district is also a point of access for beachgoers and residents from central Sydney to many of the city’s popular coastlines.

The attack was a rare occurrence in Australia.

The stabbing at the shopping center was the worst act of mass violence in the country since 2017, when a man intentionally drove his car into a mall in Melbourne, killing six people, after he had stabbed his brother and taken a woman hostage.

After a mass shooting that left 35 people dead in the Tasmanian town of Port Arthur in 1996, lawmakers tightened gun restrictions and standardized the laws across the country.

“In this country, this stuff shouldn’t happen,” Mr. Dunkley said. “People come here because it’s safe.”