LINCOLN, Neb. (AP) — State officials have issued a health alert for two lakes in southeast Nebraska.

The two lakes are Rockford Lake, which is southeast of Beatrice in Gage County, and Swan Creek Lake No. 5, which is near Tobias in Saline County.

Officials say water samples showed high levels of a toxin released by blue-green algae. The levels exceeded the state’s threshold.

Some types of toxic blue-green algae can produce dangerous toxins.

People can still camp, fish and boat on lakes under an alert, but they should not have full-body contact with the water.

Drinking toxin-tainted water can cause vomiting, diarrhea, respiratory failure and, rarely, death.