A 47-year-old man was charged Friday in the gruesome deaths of his ex-wife and two others in New Mexico.

Sean Lannon is already in custody in New Jersey for allegedly beating a 66-year-old man in the state to death with a hammer and allegedly admitted to killing another 60-year-old man in New Mexico but has not been charged in that death.

He also claimed to have killed 11 others in New Mexico but police have said there were no records of people missing from the area or other police reports that would indicate there are more potential victims.

Lannon allegedly shot his ex-wife, Jennifer Lannon, 39, at the home they lived in while they were married in Grants, New Mexico, after he claimed she was having an affair with Jesten Mata, 40. The couple divorced in 2019. 

SEAN MICHAEL LANNON, MAN KINKED TO 5 MURDERS, ADMITS TO KILLING 16 PEOPLE 

Lannon was apprehended in St. Louis earlier this month in connection with the deaths of five people across two states.

Lannon was apprehended in St. Louis earlier this month in connection with the deaths of five people across two states. (Gloucester County (N.J.) Prosecutor's Office)

He told police his ex-wife and Mata had given his children drugs to get them to sleep. He said that after Mata left, Jennifer began to panic because she thought the children were dead.

According to the affidavit, Lannon claimed Jennifer tried to overdose on heroin, saying she couldn't live without the kids. He said she still had a pulse so he shot her in the head. He told authorities he planned to kill himself but then heard one of the children cry out and put the gun down.

Lannon told investigators that he put Jennifer's body in a container and placed it in the backyard.

He said a week later he lured Mata back to the house using his ex-wife’s phone and allegedly shot and killed Mata after he showed Lannon a sexually explicit photo with one of Lannon’s kids. Police said there is no evidence Mata had sexual photos with the kids.

A week after that, Lannon said he killed Matthew Miller, 21, who he claimed had sold drugs to his ex-wife and Mata.

Lannon allegedly dismembered their bodies with handsaws and knives and stuffed them into plastic bins.

He initially allegedly lied to officers, telling them the three had run off with a bag of drugs. Friends also unknowingly helped him move the bins along with his other belongings to Albuquerque in mid-February, according to court records.

The remains of Jennifer Lannon, Mata and Miller were found in early March inside a pickup truck at a parking garage at the Albuquerque airport. The body of the truck's owner, Randal Apostalon, 60, was also found. Lannon allegedly told police he killed Apostalon after asking him for help moving the containers and for money.

In New Jersey, Lannon is accused of breaking into the Philadephia-area home of Michael Dabkowski, 66, and beating him to death with a hammer. He claimed Dabkowski had sexually abused him when he was a child and said he went to the home to retrieve sexually explicit photos of the two of them. That claim is being investigated by prosecutors.

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Dabkowski’s body was discovered on March 8, three days after the remains of the other four were found in New Mexico. Lannon was driving Dabkowski’s car when he was arrested by U.S. Marshals on March 10 in St. Louis, Missouri. Authorities aren't sure why he was in the state.

Sean Lannon had been awarded sole custody of the couple’s three children in 2019 and his ex-wife was only allowed supervised visits over concerns about the potential for neglect due to prescription drug abuse, court records show. 

Relatives say Sean Lannon flew to New Jersey in early March with the couple’s three children — 6- and 7-year-old girls and a 4-year-old boy. He dropped them off with relatives, claiming he was going back to look for his ex-wife. Her family already was worried, saying it wasn’t like her to leave without lettign soemoen know. 

The couple lived in New Jersey before moving to New Mexico. 

The Associated Press contributed to this report.