Drug Enforcement Administration officials say they wrapped up the largest investigation of illegal steroid use in U.S. history early this morning. An investigation that, they say, leads directly back to China.
Sources tell ABC News that a series of raids across the United States uncovered an extensive underground network of illegal laboratories and large-scale marketing operations via the Internet.
More than 56 labs were targeted, with more than 120 arrests made in New York, San Diego, Providence, Kansas City and Houston.
Operation Raw Deal allegedly discovered millions of doses of anabolic steroids, human growth hormone and other drugs worth tens of millions of dollars.
Investigators say they identified more than 30 companies in China that allegedly supplied the chemicals needed to produce steroids.
According to DEA officials, the precursor drugs from China were shipped to the United States where drug dealers would then use their labs to produce the finished steroids.
Underground Web sites, chat rooms and message rooms marketed the drugs to young people and athletes.
The magnitude of the operations uncovered suggests that the customer base for illegal steroids is clearly in the thousands. And those taking the steroids without a doctor's prescription might not realize just how dangerous they are.
Officials say the drugs are often produced in unregulated, often filthy conditions.
Anabolic steroids can have serious side effects, such as strokes, blood clots, high blood pressure, heart disease, liver damage and severe mood swings, including aggression.
The results of the probe are expected to be announced Monday in a series of press conferences around the country.