Sean Lannon

An alleged New Jersey serial killer pleaded guilty to one count of murder in the first degree on Wednesday morning. Four additional murder charges still await him.

Sean M. Lannon, 47, entered his guilty plea in a Gloucester County courtroom and accepted culpability for the 2021 murder of 66-year-old Michael Dabkowski, his mentor with the Big Brothers program in 1985. The defendant previously admitted to bludgeoning his victim to death in South Jersey – claiming Dabkowski sexually assaulted him as a child.

In an interview with law enforcement in 2021, Lannon said he traveled to the victim’s residence to obtain explicit photographs of the two together before they fought. After the fight, the photographs were handed over, the defendant said, but then he beat Dabkowski in the head with a hammer anyway. After the gruesome murder, authorities alleged, Lannon stole Dabkowski’s car and drove to St. Louis, Missouri, where he was arrested on various charges.

Under the terms of the plea agreement, the defendant will receive a 35-year prison sentence and he will be eligible for parole after 30 years, according to NJ.com. His formal sentencing hearing is currently slated for Dec. 21, 2022.

At the time of his apprehension, Lannon was wanted for five murders in two states. When he was confronted by police, however, the defendant allegedly said he had killed at least 16 people. The remaining 11 would-be murders are still something of a mystery.

The four additional known alleged victims were all found together – decomposing in a truck parked in the Albuquerque International Sunport, the primary airport serving the Albuquerque, Santa Fe and Las Vegas, N.M. areas. Those bodies belonged to his 39-year-old ex-wife, Jennifer Lannon; 40-year-old Jesten Mata; 21-year-old Matthew Miller; and 60-year-old Randal Apostalon.

In a series of jailhouse interviews, Lannon allegedly told detectives that his ex-wife and Mata were in a relationship pockmarked by drugs that went south after she allegedly feared she had drugged her three children to death while trying to get them to sleep in January 2021. Lannon said the mother tried to overdose on heroin but that didn’t work, so he shot her in the head, considered killing himself, then realized the children were not dead.

The next week, the admitted killer allegedly said, he lured Mata to the house and shot him in the back of the head. Then, a similar scene is said to have played out with Miller – who Lannon claims was the couple’s drug dealer. Another luring effort resulted in another shot in the back of the head and then another bludgeoning “to stop his gurgling sounds,” police allege the defendant admitted.

As the hidden bodies piled up in the Grants, N.M. residence, Mata and Miller were dismembered with a borrowed electric saw and then stored in plastic tote bags next to Jennifer Lannon’s intact body.

The three bodies were eventually moved to several different locations – Apostalon was hired to move them during one such incidence of those corpse-shuffling efforts and is said to have asked for more money than Lannon anticipated paying. Pressed with having to remove the bodies from his truck, the final man was killed.

Earlier this month, prosecutors considered what is known as a “global plea resolution” that would have seen all five slayings accounted for with the same plea deal, NJ.com previously reported. But the Wednesday agreement only concerns the murder of the New Jersey man.

Prosecutors in New Mexico will likely pursue those four murder charges some time after Lannon is sentenced.

The defendant is currently being detained Salem County Correctional Facility pending his final sentencing hearing.

[Image via CBS Philly/screengrab]