(CNN) Former Olympic decathlon champion and reality TV star Bruce Jenner was involved in a fatal four-car accident in Southern California on Saturday, the Los Angeles County Sheriff's Department said.

Jenner was driving a black Cadillac SUV that was the third vehicle involved in a multiple read-end collision, Sgt. Philip Brooks of the sheriff's department said.

The first vehicle was a black Prius that stopped short, CNN affiliate KCAL reported , citing deputies. Behind it was a white Lexus sedan that also hit its brakes.

Jenner's Escalade was towing a trailer with an all-terrain vehicle on it when it ran into the Lexus from behind, Brooks said. The Lexus spun into oncoming traffic and was hit by a Hummer H2. The driver of the Lexus was killed.

KCAL reported Jenner's SUV left skid marks.

The midday wreck came just after noon on Pacific Coast Highway near Corral Canyon Road, the department said in a news release.

The sheriff's department later opened a vehicular manslaughter investigation, a source close to the case told CNN legal analyst Mark Geragos. The investigation will focus on everyone in the case, not just one person, the source said.

The sheriff's department said on its Facebook page that the surviving drivers were cooperating with investigators.

A deputy said Jenner voluntarily took a field sobriety test, was questioned and went home.

Photos: Jenner's journey: From Bruce to Caitlyn Photos: Jenner's journey: From Bruce to Caitlyn Caitlyn Jenner accepts the Arthur Ashe Courage Award during the ESPYs in Los Angeles on Wednesday, July 15. In her first speech since identifying as transgender, she said she wants to "reshape the landscape of how trans issues are viewed." Hide Caption 1 of 21 Photos: Jenner's journey: From Bruce to Caitlyn Jenner, formerly Bruce, celebrates a record-setting decathlon performance at the 1976 Summer Olympics in Montreal. The victory made Jenner an instant sensation. Hide Caption 2 of 21 Photos: Jenner's journey: From Bruce to Caitlyn Jenner receives an Olympic gold medal on July 30, 1976. Hide Caption 3 of 21 Photos: Jenner's journey: From Bruce to Caitlyn Jenner poses for a portrait in 1976. Hide Caption 4 of 21 Photos: Jenner's journey: From Bruce to Caitlyn Jenner quickly found work in television. Here, Penny Marshall and Jenner take part in a taping of the "Battle of the Network Stars" TV show on February 5, 1977. Hide Caption 5 of 21 Photos: Jenner's journey: From Bruce to Caitlyn Jenner attends a celebrity tennis tournament in 1979 with Chrystie Scott and their son Casey. Scott and Jenner were married from 1972 to 1981. Hide Caption 6 of 21 Photos: Jenner's journey: From Bruce to Caitlyn Linda Thompson, who became Jenner's second wife, accompanies Jenner at the New York premiere of the movie "Can't Stop the Music" in June 1980. Jenner appeared in the movie, which was a huge dud and won the first Razzie award for worst picture. Hide Caption 7 of 21 Photos: Jenner's journey: From Bruce to Caitlyn Jenner served as an NBC sportscaster for several years. Hide Caption 8 of 21 Photos: Jenner's journey: From Bruce to Caitlyn Jenner, who was diagnosed with dyslexia while growing up, joins first lady Nancy Reagan, other celebrities and recipients of the Outstanding Learning Disabled Achiever Award at the White House in 1985. From left to right are G. Chris Anderson, Tom Cruise, Jenner, Reagan, Cher, Richard C. Strauss and Robert Rauschenberg. Hide Caption 9 of 21 Photos: Jenner's journey: From Bruce to Caitlyn Jenner, lower left, appears in a 1986 episode of "Love Boat" featuring Hulk Hogan and Tim Rossovich. Hide Caption 10 of 21 Photos: Jenner's journey: From Bruce to Caitlyn Jenner and Kris Kardashian married in 1991. It was Jenner's third marriage. Hide Caption 11 of 21 Photos: Jenner's journey: From Bruce to Caitlyn The Jenners share a bottle of champagne over a bubble bath. Hide Caption 12 of 21 Photos: Jenner's journey: From Bruce to Caitlyn The Jenner-Kardashian family poses for a portrait in 1993. Kris and Jenner each had four children when they were married. Clockwise from top left, the kids are Burton Jenner, Khloe Kardashian, Kim Kardashian, Brandon Jenner, Brody Jenner, Kourtney Kardashian, Cassandra Jenner and Rob Kardashian. Hide Caption 13 of 21 Photos: Jenner's journey: From Bruce to Caitlyn Jenner carries the Olympic flame down Sunset Boulevard in West Hollywood, California, on April 27, 1996. Hide Caption 14 of 21 Photos: Jenner's journey: From Bruce to Caitlyn The Jenner family attends the premiere of "The Emperor's New Groove" in 2000. Jenner and Kris had two kids together: Kylie, left, and Kendall. Hide Caption 15 of 21 Photos: Jenner's journey: From Bruce to Caitlyn Jenner and Tai Babilonia are seen in a publicity photo for "Skating With Celebrities" in 2006. Hide Caption 16 of 21 Photos: Jenner's journey: From Bruce to Caitlyn Jenner attends the premiere of the reality show "Keeping Up with the Kardashians" in 2007 with, from left, Khloe Kardashian, Kim Kardashian, Kris Jenner, Kourtney Kardashian and Rob Kardashian. Hide Caption 17 of 21 Photos: Jenner's journey: From Bruce to Caitlyn Wheaties featured retro images of Olympic champions, including Jenner, in 2012. Hide Caption 18 of 21 Photos: Jenner's journey: From Bruce to Caitlyn Jenner hits a tee shot at a celebrity golf tournament in North Las Vegas, Nevada, in 2014. Hide Caption 19 of 21 Photos: Jenner's journey: From Bruce to Caitlyn In April, Jenner sat down for an interview with Diane Sawyer to reveal that the former Olympian has the "soul of a female." Hide Caption 20 of 21 Photos: Jenner's journey: From Bruce to Caitlyn Vanity Fair unveiled its Jenner cover shot by famed photographer Annie Leibovitz in June. Hide Caption 21 of 21

No information about the deceased was immediately available.

Jenner, 65, was not injured in the crash, publicist Alan Nierob said.

Pictures posted by TMZ showed Jenner standing by a damaged car talking with a firefighter.

Five children and two adults were taken to the hospital with injuries, authorities said.

The sheriff's department is still investigating the cause of the accident, the statement said. The accident occurred on a tricky stretch of the highway, where the road is narrow and twisting.

In a bizarre twist to the story, a car later drove through safety barriers around the scene and struck two of the cars from the initial accident, Cmdr. Mike Parker of the sheriff's department tweeted. The driver was arrested on suspicion of driving under the influence, Parker wrote.

Jenner won the 1976 Olympic decathlon with a world record score for the 10-discipline event. He quickly capitalized on his success with Wheaties commercials, appearances and other ventures.

He became an actor, appearing in the drama "CHiPs" in 1981 and occasionally playing himself on shows such as "Silver Spoons." He is best known to many television viewers as a member of the cast of the current reality show "Keeping Up With the Kardashians."