LAS VEGAS — The Air Force says it'll move forward with condemnation to acquire a remote Nevada mine property now surrounded by a vast bombing range including the super-secret Area 51.

A statement Friday from Jennifer Miller, assistant Air Force secretary for installations, says Groom Mine site owners didn't take a $5.2 million "last best offer" by Thursday's deadline.

Rachel Gregory, one of about 20 Sheahan family members and owners of the 400-acre site, says they still want to negotiate but the military won't.

Owners trace their mining and mineral claims to the 1870s.

That's decades before the government moved in for nuclear weapons testing and Air Force bombing.

The Nevada Test and Training Range now encircles the mine property, and the Air Force says it's become a security and safety risk.