NEWARK, N.J. (AP) - A dangerous species of jellyfish that has a debilitating sting has returned to a New Jersey river.

State environmental officials said 20 clinging jellyfish were found last Friday in the Shrewsbury River. The jellyfish were found in the Manasquan and Shrewsbury rivers last summer.

Clinging jellyfish stings can cause muscle weakness, pain and kidney failure in some extreme cases. A man was hospitalized after being stung while swimming in the Shrewsbury River last year.

The state Environmental Protection Department and Montclair State University have partnered to evaluate the number of jellyfish in the Shrewsbury River.

DEP officials said clinging jellyfish inhabit shallow bay water in seaweed or eel grass. Officials said people should wear waders and exercise caution.

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