Acting Interior Department Secretary David Bernhardt’s confirmation hearing on March 28 made headlines for a bizarre reason: a person wearing a mask of Gill-man from the 1954 horror movie Creature from the Black Lagoon was seated a couple of rows behind Bernhardt.

A woman who was seated right over Bernhardt’s shoulder put on a mask of the The Gill-man, commonly called “The Creature”, soon after he began his testimony. Several other masked people were scattered across the hearing room. It took the Capitol police over an hour to notice and remove the masked protestors from the hearing room.

Greenpeace USA later claimed responsibility for the act, explaining why they executed this plan, in a series of tweets.

According to Greenpeace USA, Bernhardt is a “former oil and gas lobbyist who previously worked to help corporate polluters get their hands on public lands”. A confirmed appointment in the government is likely to give him more room to exploit his position of power for personal benefits, they said. Bernhardt has been called “a walking conflict of interest” by Greenpeace USA.

The woman visible behind Bernhardt has been identified as Greenpeace USA programme coordinator Irene Kim. Another Greenpeace USA activist who was a part of the protest is Adrienne Lowry.

You can watch the full video of the hearing here.