A US man was charged on Friday with fatally beating an elderly man previously convicted of child sexual assault who he believed had stalked his young daughter in the past.

Levi Axtell, 27, was charged with second-degree murder in the death of Lawrence V. Scully, 77, who was beaten to death last Wednesday at his home in Grand Marais, Minnesota.

A criminal complaint filed on Friday said Axtell killed Scully with a shovel and a moose antler then drove to the Cook County Sheriff’s office and confessed, the Minneapolis Star Tribune reported.

At a video hearing on Friday, Axtell’s bail was set at US$1 million.

Defence attorney Dennis Shaw noted during the hearing that Axtell had no serious criminal history until now and his longtime ties to Grand Marais made him a minimal flight risk.

Axtell remains jailed in Cook County. His next court appearance is scheduled for April 10.

In 2018, Axtell alleged that Scully was stalking his 22-month-old daughter and other children in his van, which he parked near her Grand Marais daycare.

Axtell sought an order of protection, which was granted but then dismissed within several weeks, according to court records.

In 1979, Scully was convicted in Kanabec County, Minnesota, of sexually assaulting a six-year-old girl, according to Cook County Sheriff Pat Eliasen. He was released from prison in 1982.

Levi Axtell, 27, was charged with second-degree murder in the death of Lawrence V. Scully. Photo / Cook County Sheriff's Office

On Wednesday, Axtell arrived at the sheriff’s office covered in blood and “put his hands on his head and said that he had murdered [Scully] with a shovel,” according to Friday’s criminal complaint.

Deputies found Scully in his home “obviously dead from the serious nature of his head wounds”, the charging document continued.

Axtell told law enforcement that he hit Scully 15 to 20 times with a shovel and then “finished him off” with a large moose antler.

He said he had known Scully for a long time “and believed him to have sexually offended against children in the past”, the complaint read. “[Axtell] said he had observed [Scully] parked in the vehicle at locations where children were present and believed he would re-offend.”

Eliasen said on Friday there had been recent allegations against Scully, but an investigation “didn’t reveal anything. Most of the reports were regarding harassment”.