Brain Eaters, The (1958)

aka’s: Keepers Of The Earth/
The Brain Snatchers/The Keepers

A huge, seemingly alien structure has been found jutting out of the earth in Riverdale, Illinois. Sent to investigate the origin of the mysterious object, Senator Walter Powers (Jack Hill) discovers that parasites from the center of the earth have infiltrated the town, taking control of the authorities and workers. Also stars Edwin Nelson and Alan Frost. Also with Joanna Lee and Leonard Nimoy.