Provo • A Utah mining company has decided to leave rocks containing ancient petroglyphs in place rather than move them as part of an anticipated expansion plan.

The Daily Herald reports the Bureau of Land Management in August 2017 approved Kilgore Companies' submitted notice of intent to expand its gravel mining operation in Benjamin.

But that approval was halted when ancient petroglyphs were found on nine boulders inside the expansion area.

Matt Preston, Bureau of Land Management field manager for the west desert district, says the area had previously been surveyed multiple times and found to have no cultural resources such as petroglyphs.

Preston says the petroglyphs came to light after the agency received public feedback indicating there was ancient rock art in the area.

Kilgore is still working on details for a new expansion plan.