ARLINGTON, Va., July 21 (UPI) -- Officials at a U.S. online pharmacy verification service say they have identified 156 Web sites engaged in the illicit sale of anabolic steroids.

"None of the steroid Web sites we reviewed required a prescription, and none used any sort of age verification service," John Horton, president of LegitScript, said in a statement.

"Studies indicate that youth and young adults are the most at risk for illicit steroid use, and these Web sites are just a fraction of those we identified selling these drugs."

The report, by LegitScript.com and KnujOn.com, an Internet spam and criminality watchdog organization, said that steroid abuse is part of the larger prescription drug abuse problem and that Web-savvy youth can easily obtain illicit anabolic steroids.

The Web site operators often use anonymous registration services offered by the registrars, or are located outside of the United States, Horton said.

The full report is available at LegitScript.com and KnujOn.com.