Taiwanese authorities are holding a North Korean freighter suspected of carrying materials that could be used for making weapons.

Officials said the freighter, Be Gae Hong, docked at the port of Kaohsiung for refueling last Thursday. Customs authorities searched the freighter after a tip from U.S. intelligence that it might be carrying dangerous chemicals that could be used to produce nuclear weapons.

It is not yet known whether anything of that sort was found. Taiwanese officials have said they will confiscate any weapons materials if they are found.

They say the freighter, which was traveling from Bangkok, will be allowed to leave Kaohsiung after the cargo inspection.