Twenty U.S. and foreign citizens were arrested this week on charges of illegally shipping controlled substances, including narcotics and anabolic steroids, to people around the world, according to a statement by the the U.S. Drug Enforcement Administration.

The arrests were the result of a yearlong investigation by six federal agencies, including the organized crime unit of the DEA, the FBI, the Food and Drug Administration, U.S. Immigration and Customs Enforcement and the U.S. Postal Service, as well as state, local and foreign law enforcement agencies.

Dubbed Operation Cyber Chase, the investigation targeted international Internet pharmaceutical traffickers operating in the U.S., India, Asia, Europe and the Caribbean.

In the U.S., arrests took place in Philadelphia; Fort Lauderdale and Sarasota, Fla.; Abilene and Tyler, Texas; New York and Rochester, N.Y.; and Greenville, S.C.

Using more than 200 Web sites, the drug traffickers allegedly shipped controlled substances such as narcotics, amphetamines and anabolic steroids directly to buyers of all ages without a physician"s examination, which is required by U.S. law, the DEA said.

"For too long, the Internet has been an open medicine cabinet with cyber drug dealers illegally doling out a vast array of narcotics, amphetamines and steroids," DEA Administrator Karen Tandy said in the statement. "In this first major international enforcement action against online rogue pharmacies and their sources of supply, we"ve logged these traffickers off the Internet."

Criminal indictments against those arrested contain charges seeking forfeiture of 41 bank accounts valued at more than $6 million, Tandy said in a statement.