According to the magazine, the underground bunker at his Colorado property, is aimed at protecting his family against an alien invasion.

Insiders say the star has ordered a reinforced shelter from UK firm Powerhouse, which will be big enough to house 10 people, including his wife Katie Holmes, baby Suri, and his older children Isabella, 14 and Connor, 12.

"Tom is planning to build the facility under his Telluride estate," a source told US magazine Star. "It's a self-contained underground shelter with a high-tech air-purifying system."

Although reps for the actor have denied the reports, as well as claims he's fearful of UFOs, it's known his Scientology beliefs include teachings about aliens.