Authorities are investigating the stabbings of nine people inside a Minnesota mall Saturday night as a “potential” act of terrorism after an Islamic State-linked news agency claimed that the armed attacker was “a soldier of the Islamic State.”

The attack occurred inside the Crossroads Center mall in St. Cloud, about 70 miles northwest of Minneapolis.

It ended inside a Macy's store, where an off-duty police officer shot and killed the suspect.

St. Cloud Mayor Dave Kleis said the attacker lunged at Jason Falconer, a part-time police officer in Avon, west of St. Cloud. Falconer then fired shots at the suspect, who fell but got up three times before he died.

“He clearly prevented additional injuries and potential loss of life,” Kleis said Sunday. “His heroic actions are exemplary.”

Authorities didn't identify the attacker, but the Star Tribune of Minneapolis said the attacker's father identified him as Dahir A. Adan, 22.

Speaking to the newspaper through an interpreter, Ahmed Adan, whose family is Somali, said his son was born in Africa and had lived in the U.S. for 15 years. He said police raided the family's apartment, seizing photos and other materials. He said that police said nothing to him about the mall attack and that he had “no suspicion” that his son had been involved in terrorist activity, the newspaper reported.

St. Cloud police Chief Blair Anderson said police had three previous encounters with the attacker, mostly for traffic violations.

Anderson said the attacker, dressed in a security uniform and wielding what appeared to be a kitchen knife, began attacking people right after entering the mall, stabbing people in corridors, businesses and common areas.

Falconer, who was shopping when he confronted the attacker, is the former police chief of Albany, which is 15 miles northwest of St. Cloud. He is also the president and owner of a firing range and firearms training facility, according to his LinkedIn profile.

The attacker made at least one reference to Allah and asked at least one person whether he or she was Muslim before attacking him or her, according to the St. Cloud Police Department.

In a statement Sunday, Aamaq news agency said the suspect “carried out the operation in response to calls to target citizens of countries belonging to the crusader coalition.”

Richard Thornton, FBI special agent in Minneapolis, said during a news conference that the attack is being investigated as a “potential” act of terrorism, but the suspect's motive remains unknown.

Officials said there was no indication that the suspect had direct communications with the Islamic State or that the terrorist group had planned the attack or knew of it beforehand.

“ISIS has encouraged lone wolf attacks. It has also claimed past attacks that are not believed to have been planned by its central leadership,” said a police department news release, using an acronym for the Islamic State.

The mall remained closed Sunday.

Of the nine victims — seven men, a woman and a 15-year-old girl — three remained hospitalized, authorities said.

Anderson, St. Cloud's police chief, said investigators found the suspect's vehicle in the mall parking lot.

Leaders of the Somali community in central Minnesota condemned the stabbings Sunday.

They said the suspect does not represent the larger Somali community, and they expressed fear about backlash over the attack.

Minnesota has the nation's largest Somali community, with census numbers placing the population at 40,000, but community activists say the population — most of it in the Minneapolis area — is higher.

The immigrant community has been a target for terror recruiters in recent years.

Sydney Weires, who was at the mall during the stabbings, told the St. Cloud Times newspaper that she and her friends were walking down a hallway toward Sears when they heard a scream.

“I saw this security guard sprinting down the hallway toward Target,” Weires said. “He was yelling, ‘Call the cops! Call the cops!'?”

She said they later saw one man bleeding from the side of his face and another with blood on the back of his shirt.

“He was screaming at us, ‘Get the F out!'?” she said about one of the men.

“We could have been one of the victims,” Weires said. “It's insane.”

Associated Press contributed.