Chinese police seized 2.4 tons of methamphetamine in one of the country's largest drug busts, authorities in the eastern city of Shanghai said Thursday. Twenty-eight people were arrested in the joint operation with police from the southern province of Guangdong, where the drug lab was discovered, Shanghai police said in a statement. They said the hunt began with the discovery of a drug dealer in August and that evidence led police to the lab in Guangdong, AP reported.