China's Ministry of State Security says it is cracking down on alleged smuggling of rare earths materials that it says threaten national security.

China’s exports of rare-earth products jumped in June, pointing to a potential pickup in magnet supplies after government-imposed curbs that proved to be Beijing’s most powerful weapon in its trade war with the Trump administration.

China's Ministry of State Security on Friday said foreign spy agencies had tried to "steal" rare earths and pledged to crack down on infiltration and espionage targeted at its critical mineral sector,

China has prevented a Wells Fargo banker from leaving the country, the American bank said, adding to concerns about travel there as tensions with Washington remain high. A Wells Fargo spokesperson said the bank was “closely tracking this situation and working through the appropriate channels so our employee can return to the United States as soon as possible”.

A U.S.-based Wells Fargo banker who works in trade financing has been blocked from leaving China after traveling there recently, people familiar with the matter said.Chenyue Mao, a Shanghai-born and Atlanta-based managing director at Wells Fargo,

Wells Fargo & Co. suspended travel to China after one of its top trade financing bankers was blocked from leaving the country, the latest case of authorities imposing exit bans on staff of foreign firms.