MONTEREY (CBS SF) — Swimmers are being warned to stay out of the water at Monterey Municipal Beach after tests found high levels of bacteria, county health officials said Tuesday.

An advisory was posted after tests on water samples collected Monday found high levels of bacteria that could pose a risk of illness, according to the Monterey County Health Department.

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The bacteria can come from marine life and other animals, rainfall runoff and storm drains, or human activity, county health officials said.

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The advisory will be lifted when water samples show safe levels of indicator bacteria, health officials said. Those looking for more information can call (800) 347-6363 or go to www.mtyhd.org/beach.

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