Cosmic Swarm (1982)

Close to your outpost in space a group of dormant space termites awkens and starts building a nest. You try to stop the invasion and destroy the would-be nests the termites are building. In shooting the invaders you can destroy them, however, you cannot get rid off the already placed nest blocks as easily since they have to be energized before they can be destroyed. In order to achieve this, you have to shoot a nest block while it is still being carried by the approaching termites. If you have accomplished that the already placed blocks can be shot down - at least until you hit a termite's body and the placed nest blocks will de-energized again.