DJ A.M. and Travis Barker by Kevin Mazur/ DJ A.M. and Travis Barker by Kevin Mazur/

Former Blink-182 drummer Travis Barker and DJ AM were critically injured when their private jet crashed in South Carolina, killing the four other people aboard, authorities told The Associated Press .

Barker and Nicole Richie's former fiance, whose real name is Adam Goldstein, were reported in critical condition at a burn center in Augusta, Ga., about 75 miles southwest of Columbia, where they played a free concert near the University of South Carolina Friday night.

People magazine reports that Barker's ex-wife, Shanna Moakler, has rushed to the drummer's side. Barker's former mother-in-law Gail Moakler told People, "Shanna flew out this morning, and I am going to L.A. to be with the children so that she can devote time to Travis." She also said, "Our heart pours out. We're hoping he recovers. The family is rallying around him and saying our prayers." The couple's two young children Landon, 4, and Alabama, 2, have not been told.

DJ AM's mother informed his sister, Lara, and her husband, Benjamin Long, of the plane crash by phone on Saturday morning. "We're in shock," Benjamin Long told People. "Nobody expects something like this. We're waiting to hear more."

Barker and DJ AM, who appear together under the name TRVSDJ-AM, were headed back to California when their Learjet went off a runway and crashed on a nearby road, the AP reported. Air traffic controllers had reported seeing sparks during the departure.

The show, which included performances by former Jane's Addiction singer Perry Farrell and singer Gavin DeGraw, drew 10,000 people, Columbia Mayor Bob Coble said.

Farrell's manager said they didn't find out about the crash until they arrived at the airport Saturday morning to find it closed.

"I just hugged them hello less than 24 hours ago. I wish I could hug them now," Peter Kastis said.

Barker's assistant, Chris Baker, 29, of Studio City, Calif., and his security guard, Charles Still, 25, of Los Angeles, died in the crash, the county coroner told the AP. Also killed were the pilot, Sarah Lemmon, 31, of Anaheim Hills, Calif., and co-pilot, James Bland, 52, of Carlsbad, Calif.

Barker, 32, joined Blink 182 in 1998, shortly before they exploded in popularity with the album Enema of the State.

After the band's breakup in 2005, Barker joined Blink bandmate Mark Hoppus in the group (+44.)

Barker also starred in MTV's Meet the Barkers with former Miss USA , Moakler.

Barker and DJ AM performed together at MTV's Video Music Awards earlier this month. - Jennifer Holland

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