Wrestling legend Rey Misterio Sr. has died at the age of 66.

The death of Mysterio Sr., whose real name is Miguel Ángel López Días, was announced by his son, El Hijo de Rey Misterio (Miguel Aarón López Hernández), on Facebook on Friday, December 20.

“Friends and family, I am sorry to inform you that my father, Miguel Ángel López Días, Rey Misterio Sr., passed away this morning… I will keep you updated. Thank you,” said the statement, originally published in Spanish. A cause of death was not announced.

Mexican wrestling company Lucha Libre AAA Worldwide also released a statement on social media to confirm the news.

“We mourn the painful death of Miguel Ángel López Días, known as Rey Misterio Sr. We extend our deepest condolences to your loved ones and raise our prayers to Heaven for your eternal rest,” said the statement, originally published in Spanish.

Mysterio Sr. is the uncle of current WWE superstar Rey Misterio. Misterio’s son, fellow WWE superstar Dominik Misterio, reacted to his death by posting pictures of him on Instagram and writing “🖤” in the caption.

His death comes almost a month after the death of his brother (Misterio’s father), Roberto Gutierrez, on November 17 at the age of 76.

Accordingly NewsweekMysterio Sr. began his career as a boxer before making his in-ring debut as a wrestler in 1976.

He wrestled for many promotions including Pro Wrestling Revolution, Tijuana Wrestling, World Wrestling Association (WWA) and Lucha Libre AAA Worldwide.

His stardom became even more prominent when he appeared at World Championship Wrestling’s Starrcade pay-per-view at the Pat O’Connor Memorial International Cup in 1990, where he represented Mexico alongside fellow wrestling legend Konnan, Al.com reports.

Misterio Sr. won various titles throughout his run, including the Revolution Tag Team Championship, which he held with his son, the IWC World Middleweight Championship, and the WWA World Junior Light Heavyweight Championship Newsweek.

According to the outlet, outside of the ring he also helped train his son and nephew, as well as Konnan, Psicosis, Halloween and Damian 666.

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Although he was inducted into the Tijuana Sports Hall of Fame in 2006 and retired from professional wrestling in 2009, his final match would come in 2023 Newsweek.