PARIS (AP) — Greenpeace activists say they have crashed a drone into a French nuclear plant to highlight the lack of security around the facility.

The drone, which was decked out to resemble a tiny Superman, slammed into the tower in Bugey, 30 kilometers (20 miles) from the eastern city of Lyon, according to a video released Tuesday by Greenpeace.

The environmental group says the drone was harmless but it showed the lax nuclear security in France, which is heavily dependent on nuclear power, using it for about 75 percent of its energy needs.

Greenpeace has gone after France's nuclear security before in previous stunts. Last week 19 activists were handed suspended prison sentences for breaking into another plant in November 2017.