UNIVERSAL CITY, CALIF., SEPT. 4 -- A fire erupted tonight on several sets at Universal Studios, forcing evacuation of at least one sound stage, and officials said they were investigating reports that a bomb may have sparked the blaze.

No injuries were reported, and the fire was contained within a half hour after it broke out. The blaze destroyed several three-story sets, according to county dispatcher Paul Evans.

City fire spokesman Jim Wells said he did not know how the fire started, but the Sheriff's Department said reports of an explosive device were being investigated.

"Nothing has been confirmed," said sheriff's Sgt. John Andrews. "We are trying to figure out whether there was or was not a bomb."

One of the burned sets was used in the 1960 movie "Spartacus," starring Kirk Douglas, a county fire dispatcher said.

Firefighters remained at the scene to mop up debris.

No one was taking the Universal City studio tour at the time of the fire, said studio spokeswoman Joan Bullard.

"The fire started ... on the back lot," she said. "It was deserted. There was no production going on at the time. We understand that quite a bit of our European area was affected."

However, Marilyn Reiss, a publicist for actress Donna Pescow, who was taping a television series for the fall called "Out of This World" at the time of the fire, said people working on sound stages had been ordered to evacuate.

"There is smoke everywhere and they ordered us to leave," Reiss said