Updated: 6:30 p.m. | Posted: 3:56 p.m.
The FBI's Joint Terrorism Task Force is now leading the investigation into the mass stabbing Saturday at a St. Cloud mall.
Authorities say 20-year-old Dahir Adan wounded 10 people before an off-duty police officer fatally shot him. Special Agent in Charge Rick Thornton has said the FBI considers the attack a "potential act of terrorism."
FBI spokesman Kyle Loven says it's customary for the Joint Terrorism Task Force to take over in such cases, and St. Cloud police will continue to help.
"The decision was made by both agencies, given the fact that the JTTF handles these types of methodical, long-range investigations," Loven said.
Peter Ahearn, a law enforcement consultant who spent three decades with the FBI but is not involved in this investigation, says a major focus will be any phone and social media activity.
"They're going to look and see how deep this person went and how far back. They're also going to do that with his computer if he had one at home," Ahearn said. "They're going to exploit that computer and look for pretty much the same thing, to see if they can find a trail to understand why this happened."
Adan was a recent college student and had worked part time. He was said to be a high school honors student. He had nothing more than a minor traffic citation on his record.
A Somali community advocate who spoke with Adan's parents said he was going to the mall to pick up an iPhone.
Those who know Adan say he was a calm, cool guy, and they are trying to figure out what pushed him to violence.
The Associated Press contributed to this report.