NASHVILLE, Tenn. -- Wildlife officials are looking into the mysterious deaths of fish and birds at Nashville's Centennial Park on Sunday.

Park police said they found at least 25 geese and ducks that were either dead or dying at a park pond. Also, hundreds of fish were found dead. It is unclear what caused the animals to suddenly die, but tests are being done on the animals.

Metro workers said they have seen natural deaths at the park in the past but never to this degree.

"A duck just popped up out of the water and shook for a second and then died, and then a minute later another one died," said park visitor Nona Hilton on Monday.

Metro park officials expect to have some test results on what is causing these deaths in the next couple days. Officials said Centennial Park is still safe but advise against fishing in the pond.

Metro and state officials said they are looking into whether someone is hurting the animals on purpose.

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