More than 120 people were arrested in an 18-month international investigation of illicit steroid labs, the Drug Enforcement Administration announced Monday.

The DEA said the wide-ranging probe dubbed Operation Raw Deal was assisted by foreign governments in nine countries including China and led to the seizure of 56 laboratories in the United States for manufacturing anabolic steroids and human growth hormone.

DEA spokesman Michael Sanders said 143 federal search warrants were issued during the probe, many of them since last Thursday.

The number of steroid doses seized in the raids amounted to 11.4 million.

Investigators seized over 500 pounds of raw powder originating in China and used to manufacture steroids.

"China really stepped up to the plate to help us in this investigation," DEA spokesman Garrison Courtney said in Washington.

News conferences by law enforcement officials were planned for San Diego, New York City, Houston, Kansas City and Providence, R.I., said Sanders.

In addition to China's cooperation, other countries participating in the investigation were Mexico, Canada, Australia, Belgium, Denmark, Germany, Sweden and Thailand.

The seizure of steroid labs follows scandals in the sports world over steroid abuse.

Major league baseball home run king Barry Bond's career has been tainted by allegations of steroid abuse.

Pro wrestler Chris Benoit killed his wife and young son and hanged himself. At the time of his death, Benoit had more than 10 times the normal level of testosterone in his system. Ten performers suspended by World Wrestling Entertainment were punished for ordering drugs, mostly human growth hormones, that violate the company's drug policy.

Also participating in Operation Raw Deal were the FBI, Internal Revenue Service, U.S. Immmgration and Customs Enforcement and the National Drug Intelligence Center.

In Denmark, police raided 26 locations across the country. Germany's Federal Criminal office said its agents closed down five illicit labs and confiscated tens of thousands of illicit tablets and capsules as part of searches carried out in five of the nation's 16 states.

Joergen Isalin of the Denmark National Police investigative center, said police were able to see the China link in the investigation through money transfers between a buyer and a Chinese seller.