New information has emerged that confirms human remains found near a secluded wooded area belong to Travis Decker, a 32-year-old father accused of killing his three daughters at a campsite in Washington state earlier this summer.

The Chelan County coroner announced that it is impossible to conduct an autopsy on Travis Decker due to the limited remains. As a result, it is unlikely that the time and cause of his death will ever be discovered.

Authorities reported that they have not located the torso or skull, and no biological tissue was preserved. The coroner explained that because of the duration he had been deceased, paired with the summer climate and animal interference, only a small portion of his bones were left.

The video above is from a previous report.

The fragments found were dispersed across five distinct locations and were separated by several hundred yards. A state anthropologist concluded there were no bone fractures consistent with a fall, but the exact cause of Travis Decker’s death might remain unknown.

Both the DNA from clothing and the human remains found on September 18 were confirmed to be a match to Travis Decker, stated Chelan County Sheriff Mike Morrison on Thursday.

“We hope that you can rest easy at night knowing that Mr. Decker is accounted for,” Morrison said.

The remains were found during a search south of Leavenworth, the Chelan County Sheriff’s Office announced on Sept. 18.

Following the discovery of the remains, Decker’s ex-wife’s attorney expressed that the family was “hoping the remains found are indeed those of Travis.”

“We continue to be grateful for law enforcement’s efforts in this case and are forever appreciative of the entire world’s love, compassion, and support for Whitney,” Arianna Cozart, Whitney Decker’s attorney, said in a statement.

Decker, an Army veteran, was wanted for three counts of first-degree murder and three counts of first-degree kidnapping, police said.

The U.S. Marshals Service, which was previously offering a reward of up to $20,000 for information leading directly to Decker’s arrest, declared Decker to be dead in a court filing obtained by ABC News on Wednesday.

“The United States Marshals Service has advised the Defendant TRAVIS CALEB DECKER is deceased,” according to the document, which was filed to dismiss the case and quash the arrest warrant for Decker.

His daughters — Paityn Decker, 9; Evelyn Decker, 8; and Olivia Decker, 5 — had left home for a planned visitation with him on May 30, and never returned, officials said. Three days later, the girls were found dead near the Rock Island Campground in Chelan County, Washington, following a search, police said.

The girls were each found with plastic bags over their heads and their wrists were zip-tied, according to court documents previously obtained by ABC News.

An autopsy determined the girls’ cause of death to be suffocation, and the manner of death was homicide, the Chelan County Sheriff’s Office said on June 9.

Decker’s truck was recovered at the scene, but he was not found, sparking a massive manhunt. DNA found at the scene, including bloody handprints found on the tailgate of Decker’s truck, confirmed to officials that he was the sole suspect.

Hundreds of people from dozens of agencies and organizations were involved in the manhunt. Throughout the search efforts, multiple possible sightings of Decker were reported to officials, including two in Idaho — one on June 4 and another on July 5 — and one in Washington on Aug. 1, with all three proving to be unsuccessful or turning out not to be Decker.

Decker allegedly had some “mental health issues and some instability in his life” that led to restrictions regarding overnight visitation and taking his daughters out of the area, but before the girls disappeared, “there were no red flags,” Cozart told ABC News in June.

Cozart also said Decker allegedly struggled with post-traumatic stress disorder and was unable to receive help through veterans’ resources.

Nearly two months into the search for Decker, officials said they were scaling back the manhunt amid a “decrease in leads and tips,” but encouraged “everyone venturing out into these areas remain vigilant and report any suspicious activities.”

Previously, Chelan County Morrison had told ABC News they were not going to give up on the case.

“We could be in a fight for five years, 10 years, 20 years. I certainly hope we’re looking at a couple weeks and it closes out, but it could be a long time, and we are committed to staying with it,” Morrison told ABC News in July.

In August, the FBI announced it would be conducting an investigation at the campground where the girls were found dead, with officials finding “several items,” including bones. However, they were ultimately determined not to be human.

“We will not relent. We will not give up,” Morrison said during a press conference on Aug. 25. “The girls would not want us to give up.”

At a memorial held for the three children back in June, Whitney Decker described them as having “warm and open hearts.”

“I’m so thankful for the time that I had with the girls. I truly hope that the legacy of the girls’ lives lives in everyone’s hearts forever. They were incredible,” Whitney Decker said at the time.

ABC News contributed to this report.