Silent Warnings

Silent Warnings aka Dark Harvest is a 2003 scifihorror TV movie about a group of college students who begin finding crop circles by the house theyve moved into. Following the disappearance of one of them, they begin suspecting something sinister. It was commissioned by Syfy then known as SciFi Channel, written and directed Christian McIntire, and stars Stephen Baldwin, A. J. Buckley and Billy Zane. The project was released on DVD as Warnings by WL on June 23, 2003 and as Silent Warnings by Universal on August 26, 2003.

The group also finds crop circles in the nearby cornfield. When Iris suddenly disappears, they realize something is really wrong. During a blackout, the house is attacked by aliens. The group figures out the aliens are allergic to iron, which is why Joe had covered the house in it to keep them out. They attempt to fight the aliens off, but the house is eventually blown up with Layne, Macy, and Katrina the only survivors.In the end, they drive off, listening to the radio. They hear a news report stating that the blackout they experienced affects five western states and parts of Canada. They also hear that people everywhere are being attacked by strange creatures. ........

Source: Wikipedia