Former 49ers defensive end Aldon Smith, the franchise’s single-season sack record holder who missed four seasons of his career due to a series of legal issues, has died at 36.

The team announced the news Saturday afternoon. A cause of death was not known at the time of publication.

“We are devastated by the sudden and tragic passing of Aldon Smith,” the 49ers said in a statement. “Aldon’s undeniable talent and sheer dominance on the field were on display from the moment he joined our organization, having recorded one of the best rookie seasons the National Football League has seen.

“Beyond his excellence as a player, Aldon will be remembered for his infectious smile that lit up every room he walked into. Our entire organization sends its deepest condolences to the Smith family and all who knew and loved Aldon.”

Smith, a first-round draft pick in 2011, delivered one of the best starts for a pass rusher in NFL history. He notched a league-record 33 ½ sacks over his first two seasons — 14 in 2011 and 19 ½ in 2012 — before dealing with legal troubles that ultimately ended his tenure with the 49ers (opens in new tab).

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Smith played for the Oakland Raiders in 2015 and then returned after being out of the league due to a series of suspensions to play for the Dallas Cowboys in 2020 (opens in new tab).

Smith was first arrested in January, 2012 under suspicion of driving under the influence in Miami Beach, Fla., and was reportedly stabbed at a party where two people were wounded by gunshots (opens in new tab) in July 2012.

The following season, he set a 49ers’ franchise record with nearly 20 sacks. The Smith tandem of a young Aldon Smith and veteran defensive tackle Justin Smith — who also played his college ball at Missouri — dominated opposing offenses as the 49ers made it all the way to the Super Bowl.

But Aldon Smith was arrested multiple times during the remainder of his 49ers tenure and served a nine-game suspension at the start of the 2014 season (opens in new tab) for violations of the NFL’s personal-conduct policy and substance-abuse policy. The 49ers cut Smith after his third DUI arrest in 2015.

The NFL suspended Smith for a year in November, 2015, and Raiders coach Jack Del Rio became a vocal critic of a league policy that prohibited teams from having direct contact with suspended players.