By ALICIA A. CALDWELL

Associated Press

WASHINGTON (AP) -- The Drug Enforcement Administration and other federal agencies served hundreds of search and arrest warrants across the U.S. Wednesday in what officials described as the largest ever crackdown on those who make and distribute synthetic designer drugs.

DEA Chief of Operations James Capra said drug and other agents served 150 arrest warrants and 375 search warrants and seized bank accounts in 35 states as part of a seventh-month investigation. Capra said U.S. Customs and Border Protection officers have helped authorities seize more than 1,000 kilograms (2,000 pounds) of drugs used in synthetic marijuana, bath salts and other substances that can mimic cocaine, LSD and other drugs.

The drugs, often marketed as herbal incense or other seemingly innocuous products, are marketed to teenagers and young adults in a growing industry that has netted millions of dollars from traffickers, Capra said. Use of synthetic drugs has led to increases in emergency room visits around the country and routinely leads to a dangerous psychosis, he added.

"What they (traffickers) care about is lining their pockets on the backs of young people," Capra said.

Untold millions in profits have ended up in Middle Eastern countries, he said.

"The bad guys need money to fund their operations," said Derek Maltz, who heads DEA's special operations division. "The bad guys need money to ... buy their explosives, to buy their guns."

Neither Maltz nor Capra would name the countries or any criminal or terror groups that might be profiting from the sales of the synthetic drugs, citing an ongoing investigation

Agents from Homeland Security Investigations, an arm of Immigration and Customs Enforcement, were also part of the investigation, which had previously led to more than 75 arrests and the seizure of nearly $15 million in cash and assets. Agents in Arizona also recovered a stash of weapons during operations Wednesday.