The suspect was jailed in Decatur, Ill., on suspicion of second-degree murder in the death of Jay Boughton, 56, who was shot July 6 while driving south on the highway. Although authorities identified the suspect during a news conference, the Star Tribune generally does not identify suspects before they are charged.

Plymouth Police Chief Erik Fadden said the man was arrested Aug. 24 and jailed in the central Illinois city of Decatur, where he remains until he can be extradited to Hennepin County.

As of Thursday afternoon, court records did not show whether the suspect had been charged, and Fadden declined to comment on when a criminal complaint would be filed. He said the man has a criminal history but did not offer further details.

Fadden declined to disclose how detectives tracked down the suspect and said the investigation remained "very active." Police did say the man was arrested without incident about 10:40 a.m.

"This was truly a needle in a haystack that our detectives, the public — primarily our detectives — they never stopped digging and working and knocking on doors and reviewing video after video after video," Fadden said.

"And finally, you get that little break every once in awhile, and it leads to something else, and you're off to that and knocking on more doors. It really was the hard work of our detectives that got us down to Illinois."

Fadden has previously said a traffic encounter between the two drivers "escalated quickly," and the shooter killed Boughton, of Crystal, over something possibly as minor as a lane change.

The chief preferred not to use the term "road rage" in describing what happened. "It was really just a senseless act that happened in a brief moment when two vehicles were next to each other. … This isn't what I would ever classify as a 'road rage' or back and forth," Fadden said.

Boughton was shot in the head at 10 p.m. as he drove on Hwy. 169 near Rockford Road on the eastern edge of Plymouth. His vehicle then went through a fence and crashed into the parking lot of an apartment complex in the 3900 block of N. Lancaster Lane, where his 15-year-old son, Harrison, gave him CPR.

Traffic surveillance video in the moments leading up to the gunfire showed the shooter's SUV heading west on Interstate 694 near N. Snelling Avenue in Arden Hills before exiting onto southbound Hwy. 169, and then pulling up on the left of Boughton's vehicle and briefly pacing it before the shooting.

The suspect's vehicle, a late-model Chevy Suburban, was located July 23. Police initially did not say where the SUV was found or what led them to it. However, Fadden said that "locating that vehicle certainly provided information for our detectives to move in a direction and get where we are at today."

The chief also declined to specify whether the suspect owned the SUV or was connected to it in some other way.

He said tips are still welcome as the investigation continues beyond the more than 1,500 hours that members of law enforcement have put into finding the suspect.

Agencies involved in the arrest included officers from the Plymouth and Decatur police departments, and agents of the U.S. Marshals Service, "who did a wonderful job in safely getting a dangerous suspect into custody without any type of incident or any type of injury," Fadden said.

He said that Boughton's family was notified of the arrest on the day that it occurred.

"They were grateful," the chief said. "I would never use the word happy because there's nothing happy or great about this situation, but grateful and definitely a sense of relief from the family members that I spoke with personally on the phone. They were just appreciative that there is some sort of closure at this point."

Fadden said that informing the family about the arrest "was a bright moment in this last eight weeks. It's been a tough and tiring and exhausting eight weeks.

"It was nice to be able to have a good phone conversation with a family that has had nothing but bad news," he said.

A relative who has acted as a spokesman for the family at previous police news conferences did not immediately return messages for comment or release a statement.

"This doesn't do anything to bring Jay back, clearly," the chief said, "but I think it does help the family understand that they're not going to be wondering forever what happened or who's responsible for this."