Prison-yard pot plagues Japanese lockup

TOKYO - A Japanese prison is scrambling to eradicate marijuana plants that keep sprouting up on its exercise ground, officials said Tuesday.

The marijuana plants started sprouting at Abashiri Prison on Japan's northernmost island of Hokkaido about a year ago, said prison official Takeshi Okamura. He said officials plucked out as many as 300 marijuana plants and treated the ground last year, but several more sprouted again this year.

Prisoners reported them to the guards.
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Local botanical experts concluded the marijuana seeds were inadvertently brought in with the soil used for the exercise ground, Okamura said.

"It's a headache," Okamura said. "This isn't a farm."
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Inadvertent my ass. Wonder if they ever heard of Round-Up.