SYDNEY - Beaches in Sydney including the iconic Bondi were closed to bathers on Thursday after hundreds of black balls suspected to be toxic washed up on the city's shores.

Waverley Council said it had closed Bondi, Bronte and Tamarama beaches as a precaution, while neighboring Randwick Council has closed an additional four beaches to the south.

“The wellbeing of our community is paramount. That's why Council has taken the precaution to close our beaches,” Waverley Mayor Will Nemesh said in a statement.

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Preliminary testing by Randwick Council suggests the mystery items were “tar balls” – lumps of oil and debris.

New South Wales state's Environment Protection Authority said it was conducting its own tests, advising against swimming near or touching any of the balls.

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Sydney is home to over 100 beaches in its harbor and along its oceanfront that are famous across the world, attracting millions of tourists and locals each year.