The FBI is involved in the investigation. "We are working in concert with the St. Cloud Police Department," Minneapolis FBI field office spokesman Kyle Loven told The Washington Post. "Right now we're trying to ascertain the facts."
Loven would not comment on the Amaq claim or on the identity of the suspect.
During a news conference on Saturday night, St. Cloud Police Chief William Blair Anderson declined to call the attacks an act of terrorism. The suspect's motive remains unknown, he told reporters. A spokesman for the police department has not returned a call from The Post inquiring about a possible link to the terrorist group.
"I want everyone in St. Cloud to know we will be diligent and get to the bottom of this," Anderson told reporters. "Starting tomorrow, St. Cloud will not be the same anymore."
It's unclear at this time if the terrorist group had planned the attack or knew of it beforehand, according to the most recent news release from the St. Cloud Police Department.
"IS has encouraged lone wolf attacks. It has also claimed past attacks that are not believed to have been planned by its central leadership," according to the department.
Many of the attacks that the terrorist group has claimed since the highly coordinated shootings and bombings in Paris last November were carried out by individuals who were simply inspired by the group's ideology and likely never came into direct contact with ISIS operatives, The Post's Max Bearak wrote in July.
The attack happened on the same night that an explosion happened in the Chelsea neighbourhood of Manhattan in New York City. At least 29 people suffered non-life-threatening injuries in the blast. One person was seriously injured, authorities said.
Hours earlier, a pipe bomb exploded in a Jersey Shore garbage can shortly before a scheduled charity race benefiting Marines and Navy sailors.
On Friday, in Philadelphia, a gunman fired 18 shots at a police officer before shooting several others, including a woman who was killed.
Authorities say none of the incidents appear to be related.