MANCHESTER, NH (CBS) – Police are investigating a series of gasoline thefts over the weekend in which thieves drilled holes in pick-up truck tanks to siphon out gas.

Manchester Police say on Monday morning, the owner of Empire Automotive Group found four pickup trucks parked in the parking lot with holes in their gas tanks.

The trouble was first spotted when a customer was interested in one of the trucks. But when workers brought it over, the truck suddenly ran out of gas.

Upon closer examination, police determined the gas tanks to the vehicles had been drilled out, and the gas was drained and apparently stolen.

“Its a significant hit for us, not so much for the gas – if that’s all that was taken it really wouldn’t have been that big of a problem for us,” dealership owner Randy Miller said.

Miller says replacing the tanks will cost around $7,000.

The dealership will beef up security with added lighting and cameras.