Federal agents raided Oaksterdam University, a medical marijuana training school founded by Richard Lee, on Monday morning, according to the Associated Press.
The doors to the school, located in the San Francisco Bay area, were barred by US marshals after morning raids conducted by the Internal Revenue Service and the US Drug Enforcement Administration.
Protesters gathered as agents carried trash bags full of unknown materials out of the school, said the AP. A museum and a medial marijuana dispensary operated by Lee were also raided.
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Time magazine said the agents carried away dozens of marijuana plants concealed in bags. According to Oaksterdam officials, Lee and four other school administrators were detained temporarily.
Protesters showed up after the raid, shouting slogans and waving signs that demanded an end to the crackdown on pot. Some of the protesters were openly smoking pot, said Time.
The school, called the "Princeton of Pot" by some, trains students on how to grow, harvest and sell pot, according to Bloomberg. Oaksterdam was founded by Lee in 2007, after medical marijuana was legalized in California.
The federal raid was the latest in a series of crackdowns by the Justice Department on the marijuana business that still violates federal law, despite being legal in California.
University officials were confident that the school would reopen, saying they planned for classes to resume normally on Wednesday, according to NBC.
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