The homeless drifter accused of gunning down a retired couple on a hiking trail in New Hampshire camped out in the woods near their home for months, according to documents, living on Mountain Dew soda and propane-fueled cooking.

He purchased supplies at Walmart and other local stores and ordered supplements online, having them, delivered to a FedEx drop box, according to authorities.

Then in April, Logan Clegg, a 26-year-old vagrant who killed a Washington man in 2018, allegedly Gunned down Stephen and Djeswende "Wendy" Reid, a couple in their 60s who had moved to Concord, New Hampshire, to enjoy retirement.

Vermont police arrested Clegg at the South Burlington Public Library on Oct. 12, according to court documents, on an outstanding Utah warrant. They traced him there through purchase records and phone pings after Homeland Security Investigations discovered he’d booked a one-way ticket to Germany that would have left on Oct. 14.

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While he sat in a Vermont jail, police served a search warrant on his belongings and found enough evidence to convince a Merrimack County judge to sign a new murder warrant for his arrest in the Reids’ deaths.

Shortly after the Reids were reported missing on April 18, police canvassed the area and encountered a vagrant camping in the woods who gave his name as "Arthur Kelly," according to court documents, which noted he was seen carrying multiple cans of Mountain Dew soda.

Police found the Reids dead of multiple gunshot wounds along the trail three days later.

Police returned to the trails looking for Kelly, whose real name was later determined to be Logan Clegg, but he’d packed up camp and vanished. They checked nearby stores to see who had recently purchased a large amount of Mountain Dew – but a person of interest who appeared on video at a nearby Walmart could not be positively identified. So they dubbed him "Mountain Dew Man." 

At an abandoned campsite near the crime scene, police said they found a burnt tent, 155 small propane tanks, dozens of Mountain Dew and Coca Cola cans – and 19 spent shell casings of the same brand and caliber as the ones they recovered near the Reids’ remains. They recovered a corresponding bullet in the dirt nearby.

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A witness came forward and told police she had seen the Reids on the trail while walking her dogs the day they were killed.

She said that around five to 10 minutes after she passed them, she heard what she believed to the sound of a handgun firing five times.

A few minutes after that, she saw a young man matching Clegg’s description on the trail, who was looking "back and forth at her and at the woods."

Based on the witness’ account and her cellphone data, police said they could narrow down the Reids’ window of death from between 2:54 and 2:59 p.m. on April 18.

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Other local residents told police they’d seen a drifter camped in the New Hampshire trail between November 2021 and April 2022.

He was "clean-shaven" and "neat in appearance" but "unfriendly to others," according to the affidavit. And no one remembered seeing him after the double slaying.

The "Mountain Dew Man," however, appeared on surveillance video at a nearby supermarket on the day of the murders – which helped police identify him as both "Arthur Kelly" and, ultimately, their suspect Logan Clegg.

As they continued to investigate his purchases, they found he bought a new tent at Walmart the day after the murders – and after his campsite had be burned to the ground. He did not return to the store after that, as far as they could tell.

According to court documents, after his arrest police obtained a search warrant for his backpack and found a 9 mm Glock 17 handgun and more ammunition that matched the casings found in Concord.

Clegg’s Utah charges stemmed from a shoplifting arrest in Salt Lake City in 2020, according to court documents. When police arrested him at the time, they took a .45-caliber handgun out of his belt, and he allegedly told them "three on one" was unfair and that he wished he’d had "a chance to pull [the gun] out and fight one on one," according to the affidavit.

He added that he would "rather die than f---ing go to prison."

Salt Lake City police later discovered that the gun had been stolen two weeks earlier from a sporting goods store. 

Days after his arrest in Salt Lake City, police in nearby Logan, Utah, arrested him during burglary in progress call. They found another handgun, stolen from the same store, in his belt.

He was jailed for four days and sentenced to three years of probation.

Prosecutors declined to prosecute the slaying in Spokane, Washington, in 2018, after he claimed it was self-defense, and they found no evidence to the contrary.

In New Hampshire, Clegg will face two counts of second-degree murder.

He is being held without bail.