LOS ANGELES – Clay Tepel knew there were risks to setting up a medical marijuana shop: it could lose money, be robbed or be raided by authorities.

Still, he wasn’t expecting the phone call one August day when a voice said the police were outside and he needed to open up or they would bust down the door. His first thought, that it was a joke, turned to terror when he opened the door.

Heavily armed officers in helmets, bulletproof vests and, oddly enough, Bermuda shorts stormed his store, handcuffed him, disabled security cameras and seized his drugs before taking him to jail. When he asked why his shop was invaded, an officer responded, ‘We’re closing them all down.’

Those words could prove prescient after Los Angeles County District Attorney Steve Cooley said last week he wants to shutter clinics that sell pot for profit. Cooley’s plan is the latest salvo in a prolonged conflict in California over whether medical marijuana is truly having its intended effect or is being abused by the larger population.

Until recently, raids on clinics typically led to federal prosecutions, but Cooley’s remarks and similar ones from Attorney General Jerry Brown signal a new approach to clear the haze left by Proposition 215, the 1996 state ballot measure that allowed sick people with referrals from doctors and an identification card to smoke pot.

‘Everybody is scared,’ said Tepel, who has spoken with other pot store operators. ‘Why are voters’ rights being stepped all over? This kind of blind justice has to stop.’

The crackdown is a crushing blow for dispensary owners who were relieved in March when U.S. Attorney General Eric Holder said federal agents would only go after marijuana distributors who violate both federal and state laws.

A new policy memo issued Monday by the Justice Department told prosecutors that pot-smoking patients or their sanctioned suppliers should not be targeted for federal prosecution in states that allow medical marijuana. The guidelines do, however, make it clear that federal agents will go after people whose distribution goes beyond what is permitted under state law or use medical marijuana as a cover for other crimes.

The comments Holder made earlier this year appear to have emboldened entrepreneurs as marijuana shops cropped up across California. In Los Angeles alone, there are an estimated 800 dispensaries, more than any other city in the nation. In 2005, there were only four, authorities said.

Cooley contends a vast majority of several hundred outlets his office investigated aren’t following state law. Initially, the law allowed authorized marijuana users to grow their own plants, but lawmakers revised the law in 2003 to allow collectives to provide pot grown by members.

Cooley said he would target stores who are profiting and selling to people who don’t qualify for medicinal marijuana.

‘All those who are operating illegally, our advice to them is to shut down voluntarily and they won’t be subject to prosecution,’ Cooley told The Associated Press on Wednesday.