An interdictor is a type of attack aircraft that operates far behind enemy lines, with the express intent of interdicting the enemy's military targets, most notably those involved in logistics. The interdiction prevents or delays enemy forces and supplies from reaching the battlefront. The term has generally fallen from use. The strike fighter is a closely related concept, but puts more emphasis on air-to-air combat capabilities as a multirole combat aircraft. Larger versions of the interdictor concept are generally referred to as penetrators.