A joint Chinese-U.S. investigation has shut down a syndicate making fake drugs to sell around the world. The case highlights that property rights violations not only cost businesses millions of dollars, but they also threaten human health and safety.

Operation Ocean Crossing, which linked Chinese and U.S. investigators, confiscated 440,000 counterfeit pills. Among them was Viagra and Lipitor, a drug used to reduce cholesterol and help patients avoid strokes.

The drugs, worth over $4 million, were manufactured in China and sold on the Internet in many countries, including the United States and Europe. 11 Chinese citizens and one American were arrested in the case.

Samples of the haul were displayed for journalists recently. The fake Viagra looked identical to the genuine pill, which treats sexual dysfunction in men and is produced by the U.S. company Pfizer.

"These untested pharmaceuticals can pose significant risks to the public safety and well-being of Chinese and Americans alike," said Andy Yu, a U.S. customs officer based in Beijing.

Product counterfeiting has long been a problem in China, a manufacturing center for fake goods that are distributed across the globe.

The United States, the European Union and other governments have pressed China to protect intellectual property rights.

The World Health Organization warns that the trade in fake medicines in particular is a worsening global crisis. Most illegal drugs are produced and consumed in developing nations such as China, where impoverished people risk damaging their health with cheap fake drugs. Experts say counterfeits often either do not work or are outright harmful.

Mr. Yu urges consumers to be cautious when buying cheap drugs on the Internet. "If an item that normally costs $100 can be bought for $2, I think there is something wrong with that kind of purchase," he said.

Gao Feng is the deputy chief of the Chinese Public Security Bureau's economic crime investigation department. He says China has a tough fight against piracy, and it is one that countries must on work together.

"Difficulties that the Public Security Bureau face are generally caused by a lack of information, a lack of knowledge of IPR laws in the society, and the fact that the scale of IPR crimes has now become global, it is no longer a one-country issue, but one for the entire international community. I believe this [crackdown] is not the end but the beginning," Mr. Feng said.

Despite such joint enforcement efforts, counterfeiting remains rampant throughout China. The range of products is virtually endless, from designer clothing to software to toys. Law enforcement officials say many, such as fake foods and shoddy car parts, are potentially lethal.