7 US Marines killed in training exercise

At least seven US Marines have been killed and several others injured in a training exercise in the US State of Nevada, authorities say.

The incident occurred on Monday when a massive explosion rocked a military ammunition storage facility located at the Hawthorne Army Depot in western Nevada, authorities said.

After the explosion, four medical helicopters had been sent to transport patients to regional hospitals.

Officials refused to elaborate on the cause of the explosion and if any civilians were among the casualties.

The Hawthorne Army Depot has been used for the destruction and storage of demilitarized ammunition.

In the 1920s, a crippling explosion in the US’ main artillery depot in New Jersey called for a relocation to Nevada due to its remoteness.