DEEPHAVEN  (AP) - A study finds zebra mussels are rapidly spreading throughout Lake Minnetonka.

The Minnehaha Creek Watershed District said Wednesday it found zebra mussels present at most testing sites across the lake.

Zebra mussels were first detected there last summer. Follow-up data collected last fall found zebra mussels across much of eastern Lake Minnetonka. This spring, the district placed monitoring devices at 32 sites all over the lake.

During the first monthly check of the devices in late June, zebra mussels were found at 26 locations all across the lake. Only three sites turned up no evidence of the invaders, while monitoring devices were lost at three other spots.

Officials remind people to clean, drain and dry their boats and equipment before entering new waters to prevent the spread of zebra mussels.

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