An attorney for St. Louis County tells the Duluth News Tribune he expects to file charges against the Last Place on Earth. Police raided the shop in September and reportedly took synthetic marijuana, cash and 31 guns. The shop claims that was illegal search and seizure.

The Justice Department is throwing its support behind bills from Sen. Amy Klobuchar that would ban synthetic drugs such as "bath salts," which the senator says are dangerous but still available over store counters.

Reports that "designer drugs" can have harmful side effects don't seem to be deterring many customers. Dozens of people line up outside Last Place on Earth in Duluth every weekday to buy chemicals that supposedly mimic the effects of illegal drugs. The store's owner says he expects the chemicals will bring in about $6 million in business this year.

Over a dozen officers stormed the shop -- going through files and boxing up items. One person was arrested. The shop's owner says he's not selling any substances officially listed as banned in the state -- but acknowledged he operates in a gray area.

Officers charged in guns drawn and rounded up customers at The Last Place on Earth shop. It was part of a nationwide federal crackdown Wednesday on dealers who peddle what health experts consider the latest illegal drug epidemic: man-made chemicals designed to mimic marijuana, ecstasy and other illegal drugs.