The plant being built by Australian miner Lynas in eastern Malaysia could curtail China’s monopoly on the global supply of rare earths for making high-tech goods.

Protesters including opposition lawmakers marched Friday from Kuala Lumpur’s Petronas Twin Towers to a street near the Australian High Commission. Some carried banners that read “Go back to Australia” and “Malaysia not a radioactive waste dump site.” Lynas says the plant will have state-of-the art contamination controls. It is meant to refine slightly radioactive ore from Western Australia. The International Atomic Energy Agency is helping Malaysia investigate whether there would be any risks.