The cause of death for Adam Harrison, the son of "Pawn Stars" creator and star Rick Harrison, has been released a month after he died in a Las Vegas home.

The 39-year-old died from fentanyl and methamphetamine toxicity, a Clark County, Nevada, public information officer confirmed in an email to USA TODAY Thursday. The manner of death was determined to be accidental, the Clark County Office of the Coroner/Medical Examiner ruled.

A full coroner's report will be released at a later date.

According to a police report by the Las Vegas Metropolitan Police Department, obtained by USA TODAY on Jan. 26, Adam Harrison was pronounced dead in the guest house he was living in on the afternoon of Jan. 19. He was discovered after another resident expressed concern about him not making an appearance since Jan. 17. The landlord found him unresponsive, prompting a call to law enforcement.

Laura Herlovich, a representative for the family, said in a statement to USA TODAY on Jan. 22 that Harrison allegedly died of a fentanyl overdose. In a statement to TMZ published Jan. 22, Rick Harrison said, "The fentanyl crisis in this country must be taken more seriously."

In 2021, 107,000 people died from drug overdoses in the U.S., according to the Centers for Disease Control and Prevention.

Opioids, specifically synthetic opioids like fentanyl, are "the main driver of drug overdose deaths. Nearly 88% of opioid-involved overdose deaths involved synthetic opioids," per the CDC. According to a recent report by the laboratory Millennium Health, illicit fentanyl is increasingly being used in conjunction with other substances, such as methamphetamine.

How Rick, Corey Harrion paid tribute to Adam Harrison

On Jan. 19, Harrison announced his son's death by posting a photo of Adam and himself at a restaurant on his Instagram account. "You will always be in my heart! I love you Adam," Harrison wrote, followed by a broken heart emoji.

Corey Harrison, Adam's older brother, shared a childhood photo of the two on his Instagram page as well. "I will always love you bubba," he wrote in the post.

Rick Harrison has starred in the History Channel show with his family since 2009. It centers on family relationships and business operations of a storefront business on Las Vegas Boulevard called Gold & Silver Pawn. Adam Harrison was not featured on "Pawn Stars," although he reportedly worked at Gold & Silver Pawn at one time, according to the Las Vegas Review-Journal.

Rick's father, family patriarch, Richard Harrison, who was characterized on the show as “The Old Man,” died in June 2018 at age 77.

Fifteen years of 'Pawn Stars':A look at Rick Harrison and his family

Contributing: Ahjané Forbes, USA TODAY