LOS ANGELES — Gabby Petito, the young woman who died on an Instagram-chronicled road trip across the United States with her boyfriend, was strangled and her death was a homicide, the local coroner said Tuesday.

The body of the 22-year-old lay in the wilderness of Wyoming for up to a month before it was found in mid-September, Teton County coroner Brent Blue said.

“We hereby find the cause and manner of death to be: the cause of death by strangulation, and manner is homicide,” he said.

“Our initial determination is that the body was in the wilderness for three to four weeks.”

Petito had quit her job and packed her life into a camper van for a cross-country adventure with Brian Laundrie, starting in July, documenting their journey in a stream of social media posts.

In images shared by the couple online they are all smiles — barefoot in a canyon or surveying the ochre rocks of state and national parks.

In one YouTube video published during their trip, Petito and Laundrie are shown kissing tenderly, enjoying a sunset together and strolling on a beach.

But the young woman’s family filed a missing person report on September 11 after the 22-year-old mysteriously vanished, and Laundrie returned home to Florida without her.

Laundrie, 23, was declared a “person of interest” in the case. He declined to cooperate with police before disappearing himself.

The FBI has launched a nationwide manhunt, appealing for anyone with information about Laundrie’s whereabouts to contact them.

Domestic violence 

Details have emerged about how police in Utah responded to a domestic violence report involving Petito and Laundrie in August.

Police bodycam footage shows a distraught Petito saying she had had an altercation with Laundrie.

Speaking to an officer after their van was pulled over, Petito is seen crying and saying she struggles with mental health problems.

Petito said she slapped Laundrie after an argument, but added she meant no harm.

The police officer decided no charges would be brought but ordered the couple to spend a night apart to calm down.

Petito’s death and the subsequent disappearance of the chief suspect sparked a blizzard of media coverage both in the United States and around the world.

It also triggered debate over the disproportionate attention accorded to missing white women.

Blue, the coroner, said Tuesday there had been a “media circus” around the case.

“Unfortunately, this is one of many deaths around the country of people who are involved in domestic violence,” he said.

“It’s unfortunate that these other deaths do not get as much coverage as this one,” he added.

“There are a lot of both men and women who lose their lives and aren’t covered with this kind of media attention.”