An explosion during a training exercise at a military ammunition storage facility in (the western U.S. state of) Nevada is believed to have killed ``several'' people.
A military spokeswoman says the explosion occurred late Monday during a U.S. Marine training exercise at the Hawthorne Army Depot.
A U.S. Marine spokesman says Marines were among those killed, but declined to specify the number of dead or the cause of the explosion.
The 60,000 hectare military facility is used for storing ammunition and other military equipment.