BERLIN (AP) — Greenland police arrested a prominent environmental activist and anti-whaling campaigner on Sunday on an international arrest warrant issued by Japan.

Paul Watson was arrested when his ship docked in Nuuk, Greenland’s capital, a police statement said, adding that he will appear before a district court.

He will be brought before a district court with a request to detain him until a decision is made on whether to extradite him to Japan, the statement said.

The Captain Paul Watson Foundation said that police boarded the vessel and led Watson away in handcuffs when it stopped to refuel. The foundation said the ship, along with 25 crew members, was en route to the North West Passage on a mission to intercept a new Japanese whaling ship in the North Pacific.

“The arrest is believed to be related to a former Red Notice issued for Captain Watson’s previous anti-whaling interventions in the Antarctic region,” the foundation said in an emailed statement.

“We implore the Danish government to release Captain Watson and not entertain this politically-motivated request,” Locky MacLean, a foundation director, said in the statement.

Greenland is an autonomous territory of Denmark.

Watson, a Canadian-American citizen, is a former head of the Sea Shepherd Conservation Society whose direct action tactics, including high-seas confrontations with whaling vessels, has drawn support from A-list celebrities and featured in the reality television series “Whale Wars.”

Japan has accused Watson and Sea Shepherd of endangering whalers’ lives during operations in the Antarctic Ocean. Authorities in Costa Rica have also sought his extradition.