The Bureau of Land Management, which manages the territory where the crash occurred, said the suspension of permits for Mojave Desert Racing will remain in effect while an investigation of the accident is under way.
A call and e-mail message to Susan and James Williams, the couple who operate MDR Productions from their South El Monte home, were not immediately returned.
The spectators were killed Saturday during a 200-mile race on a 50-mile circuit in the Mojave Desert northeast of Los Angeles. Ten other spectators were injured.
Video of the accident showed spectators crowding the edge of the narrow dirt course as trucks sped by. One truck went out of control and slammed into the crowd and overturned.
Documents provided by the BLM, which issued permits for the California 200 race, show that spectator safety was the responsibility of MDR. However, the spectators were within feet of the speeding vehicles, not 100 feet away as MDR's own rules require.
The BLM also said it was reviewing future racing events in the California desert on a case by case basis to ensure all safety requirements can be met before authorizing them to go forward.
Off-road recreation "is a popular activity in the California desert enjoyed by families and responsible organized groups," the agency said in a statement. "BLM's ongoing review will be aimed at ensuring the public safety remains our first priority."
Under review is a motorcycling and all-terrain vehicle race scheduled for this weekend in the Mojave, sponsored by the American Motorcyclist Association.
"In light of the tragedy it wouldn't be out of the ordinary for BLM to check and make sure all safety precautions are met for events coming up," said Jerry Grabow, president of the AMA's 37th district.
He said his group works closely with the BLM to ensure that its events come off safely.
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