(CNN)  -- Liberia's president has declared a state of emergency after hordes of ravenous caterpillars infested the country. The African armyworm caterpillar is chewing its way through Liberia's food crops. Tens of millions of the worm-like larvae have appeared in the northern part of the country, where they are destroying green crops like cabbage and collard greens and contaminating the water supply, Liberian Information Minister Laurance Bropleh told CNN Wednesday from the capital of Monrovia. "I am not aware that they have been here before, ever, and certainly not in this great number," Bropleh told CNN. "That is why it was so overwhelming initially when we first discovered it."
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Liberia declares emergency after hordes of ravenous caterpillars infest country
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Tens of millions of the worm-like larvae have appeared in northern areas
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Up to 350,000 people in 62 communities may have been affected
Investigators suspect the caterpillars are @placeholder armyworms, the FAO said.