ST. PAUL, Minn. (AP) — Minnesota residents are being advised to avoid going into a Douglas County lake because of toxic blue-green algae.

One dog died and another became seriously ill after apparently being exposed while swimming in Red Rock Lake in west central Minnesota.

The Minnesota Department of Natural Resources reports the conditions appeared to be consistent with an early bloom of blue-green algae.

The sheriff's office said people using Red Rock Lake are strongly encouraged to prevent animals and children from going into the water.

Warmer temperatures and excess nutrients being washed into the water can cause the harmful algae blooms. Pets, livestock and humans can be at risk.

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