(CNN) -- Former college and pro football star Charles Aaron "Bubba" Smith, who went on to an acting career after his retirement from sports, was found dead at his home, the Los Angeles County Coroner's Office said Wednesday. He was 66.

Police and fire officials were called to Smith's home after "he was found unresponsive" and pronounced him dead, said Ed Winter, assistant chief of operations and investigation for the coroner.

An autopsy will be performed to determine cause of death, Winter said. However, asked if there was any reason to believe the death was due to anything other than natural causes, he replied, "Not at this time."

An imposing 6 foot 8 and 260 pounds, Smith was considered one of the most fearsome pass rushers of his day. The No. 1 overall pick in the 1967 National Football League draft, he played nine seasons in the NFL -- for the Baltimore Colts, Oakland Raiders and Houston Oilers.

Sports Illustrated gallery: The NFL goes Hollywood

He played for the Colts in two Super Bowls and was also a two-time Pro Bowl pick.

Smith was one of the anchors of an overwhelming defense that was heavily favored to win Super Bowl III. Nonetheless, the New York Jets, led by Joe Namath, defeated the Colts in the 1969 championship of pro football, widely considered one of the biggest upsets in U.S. sports history.

The Colts atoned for that embarrassment -- somewhat -- two years later in a 16-13 victory over the Dallas Cowboys in Super Bowl V, but Smith reportedly said he was so dismayed by the game's sloppiness that he never wore his Super Bowl ring.

Smith was sidelined by a severe knee injury during an exhibition game in 1972, and the next season joined the Raiders. He told Sports Illustrated in 1973 that "not playing was terrible. I didn't want to show my face in public. I don't know if it was that we were losing or what, but it almost drove me crazy."

After retiring from pro football in 1975, Smith landed small roles on TV series such as "Good Times," "Charlie's Angels" and "Semi-Tough," according to IMDb, before landing his signature role as Lt. Moses Hightower in the first "Police Academy" movie in 1984. He reprised the role in all six movies in the popular comedy franchise.

Smith was a two-time All-America defensive end at Michigan State University. He played in what the national media dubbed "the game of the century" between Michigan State and Notre Dame in 1966, a 10-10 tie that resulted in the two teams' splitting the vote for that year's national championship.

Smith was inducted into the College Football Hall of Fame in 1988, an event he called "the jewel in my crown, for my collegiate days were very special to me."

Smith was born on February 28, 1945, in Beaumont Texas. His father was a high school football coach and his mother had earned two college degrees. According to his member biography on the College Football Hall of Fame website, he said he took his parents with him when he went to speak to youth groups "to demonstrate my respect for them."