Construction workers in northern Afghanistan have unearthed a mass grave of human bones and skulls, a military official said. A military spokesman said the grisly find was discovered Monday in the Arzana Desert, where a base of the 209th Shaheen Military Corps once stood, the Revolutionary Association of the Women of Afghanistan reported Wednesday. The grave was found at a construction site for a new building, Corps spokesman Lt. Col. Muhammad Naeem said. Construction was halted after the grave was discovered. Naeem said a military medical team would investigate to determine when the grave was dug and the number of people interred.