The first time police suspected Marc Karun in connection with the Sept. 23, 1986, murder of 11-year-old Kathleen Flynn in Norwalk, Connecticut, was about two weeks after the sixth grader was sexually assaulted, strangled to death and left in woods near her middle school.
And periodically, over the course of a more than 32-year investigation, police kept returning to Karun as a suspect as they ruled out others. The investigation that started in Norwalk, Connecticut, culminated Wednesday in Karun’s arrest at his home in rural Stetson, the small town outside of Bangor where he had been living since 2013.
The key information that continually led police to Karun — and which prevented them ruling him out as a suspect even in the absence of conclusive DNA testing — came from four convictions for kidnapping or sexual assault of four separate female victims both before and after Kathleen Flynn’s murder.
According to a 55-page police affidavit filed in court in Bangor, police found similarities in how Karun carried out those offenses, and how Kathleen Flynn’s assailant sexually assaulted and murdered her.
“Several of the cases exhibit a similar geographical profile, modus operandi and rituals to the Kathleen Flynn homicide in some form,” Norwalk Police Department Lt. Arthur Weisberger wrote in the affidavit, which police used as grounds for Karun’s arrest.
The warrant police executed to arrest Karun charges him on two counts: murder with special circumstances and kidnapping in the first degree. The statute of limitations has run out on a charge of sexual assault. Karun is currently at the Penobscot County Jail until his terms of extradition are determined. He will have a bail hearing at 1 p.m. Friday at the Penobscot Judicial Center.

When the murder happened on Sept. 23, 1986 — a crime that sent waves of fear through the Connecticut city of 86,000 — Karun had already been convicted of one sexual assault of a woman he knew.
Police interviewed Karun more than two weeks after Kathleen Flynn was killed.
Karun, who lived 2 miles from where the sixth grader’s body was found, told police he was visiting some teachers and that he had spoken with the librarian at Ponus Ridge Middle School four days before the murder, on Sept. 19, 1986. But police interviewed teachers and determined that no one had seen or interacted with Karun. They went back to talk to Karun, and he seemed unable or unwilling to explain, according to the affidavit.
At that time, police had no further evidence linking him to the case, the affidavit said.
Days after the murder, investigators compared hairs from the 1986 sexual assault case in which Karun was convicted to the evidence found at the site of Flynn’s homicide. That test was inconclusive, but it did not rule out Karun as a suspect.
Police kept returning to him as a person of interest.
In 1992, the victim of that 1986 assault was at Norwalk police headquarters on an unrelated matter and brought up Karun. She told police she had asked Karun about Kathleen Flynn’s murder. While he denied killing the girl, he told the woman he was at Ponus Ridge Middle School with friends on the day of her murder.
That same year, one of Karun’s friends also told police that Karun admitted to him that he was at the middle school on the day of the murder to visit a teacher. The friend found it strange, according to the affidavit, because Karun was not “school-oriented” or particularly close with any teachers.
In 2002, Weisberger, the Norwalk police lieutenant, was transferred to the police department’s cold case unit and took over the investigation into Kathleen Flynn’s murder. According to the affidavit, he started investigating Karun, exploring whether there was probable cause to collect hair samples.
Another test the next year comparing evidence with Karun’s DNA was again inconclusive.
Police caught a break in 2017.
As investigators analyzed evidence from Kathleen Flynn’s killing, their attention again turned to Karun, and they searched for him, knowing he would be on a sex offender registry. A Google search — which turned up Karun’s page on Maine’s sex offender registry for a 1989 sexual assault conviction — led them to Maine.

Norwalk police connected with the Maine State Police and the Penobscot County Sheriff’s Office, and they presented a warrant to obtain a DNA sample from Karun.
On Oct. 3, 2017, Norwalk police Sgt. Alex Tolnay met with Karun in Bangor at the Penobscot County Sheriff’s Office and collected the swabs. At that point, Karun refused to have any further conversations with Norwalk police.
Karun did not know at that point that he was asked to provide a DNA sample in relation to the Kathleen Flynn case because police told him it was for a kidnapping conviction.
Again, the results from that test came back either negative or inconclusive. The affidavit noted that the evidence from the murder was 31 years old at that point.
Two years later, citing the similarities between Kathleen Flynn’s murder and the other sexual assaults of which Karun is convicted, Norwalk police are back in Maine, hoping to bring Karun back with them to the city where it all started.
If you or someone you know needs resources or support related to sexual violence, contact the Maine Coalition Against Sexual Assault’s 24/7 hotline at 800-871-7741.