(Reuters) - Nevada authorities on Sunday said they were investigating one death after a severe rainstorm left tens of thousands of revelers attending the annual Burning Man festival stranded in mud, and asked that they shelter in place and conserve food and water. The Pershing County Sheriff's Office in northern Nevada said in a statement that the death happened during a "rain event" on Saturday but did not provide details of the cause of death or the person's identity. "The family has been notified and the death is under investigation," the sheriff's office said. "As the death is still under ...