PARIS (AP) — Eight environmental have broken into a French nuclear power station and set off fireworks to urge better protection for nuclear waste and protest France's dependence on atomic energy.

Utilite EDF insisted that the stunt Thursday by Greenpeace had no impact on safety at the plant in Cattenom in eastern France. The company said the activists were detained eight minutes after entering the site, and threatened legal action.

Greenpeace spokesman Yannick Rousselet said the action exposed security risks because the activists reached within 100 meters (yards) of open pools of nuclear waste. Greenpeace is lobbying for France to create special bunkers over its waste pools.

French President Emmanuel Macron's government has pledged to expand renewable energy and reduce its dependence on aging nuclear plants, the source of most of France's electricity.