Saved By The Bell star Dennis Haskins′ official cause of death has been confirmed, one week after his passing at age 75.

The beloved actor died after a battle with Parkinson’s disease, according to his death certificate, as reported by multiple US outlets on Wednesday.

Actor Dennis Haskins has died aged 75. Rodin Eckenroth/Getty

According to TMZ, no one knew Haskins’ was battling Parkinsons before he died on September 27.

It’s reported the actor’s ex-wife Sarah Quinones revealed Haskins cut off communication with close confidants in recent years to hide his diagnosis.

The certificate from the Los Angeles County Department of Public Health lists Parkinson’s disease as the immediate cause of death.

The document also lists other significant health conditions that actor was facing, including depression, hypertension, and benign prostatic hyperplasia (a non-cancerous enlarged prostate), as per the outlet.

The outlet also reported Haskins, who played Principal Richard Belding in hit ’90s series for more than 10 years, spent his final years in an assisted-living facility.

Haskins’ agent Jay Schachter announced the actor’s death in a statement released to the media on September 29.

“It’s a tragic loss. Everyone loved Mr. Belding, and those of us who got to know Dennis loved him even more,” Schachter said at the time.

“He was a great person, and he loved, I mean absolutely LOVED his fans. He always had time for them, no matter what.

Dennis Haskins with his Saved By the Bell co-stars. NBC

“He was my client and dear friend for over 20 years, and I will miss him terribly.”

Schachter did not share details about Haskins’ cause of death at the time.

Per the World Health Organisation, Parkinson disease is a brain condition that causes problems with movement, mental health, sleep, pain, speech and other health issues.

Stars who have spoken openly about their Parkinson’s disease experiences include Michael J Fox, Linda Ronstadt, Billy Connelly and Alan Alda.

Born in 1950, Haskins got his start on The Dukes of Hazzard series before finding mainstream success as stern Mr Belding on Saved by the Bell.

Haskins played Principal Richard Belding in hit ’90s series for more than 10 years. NBCUniversal via Getty Images

Known for the iconic catchphrase “Hey, hey, hey, what is going on here?“, Haskins became a staple of the series, which ran from 1989 until 1993.

He continued in the role in the Saved by the Bell: The New Class spinoff, which aired for a further seven years.

Haskins’ other acting credits include roles in TV shows like New Girl, Mad Men and It’s Always Sunny in Philadelphia, and films like A Million Ways to Die in the West.

He is survived by his son, Dustin Haskins.