Mysterious black balls that washed up on beaches across Sydney contained highly infectious bacteria commonly found in faeces-infected water - but health authorities failed to alert the public.

Once again, Mars has presented us with an example of something it seems to have in abundance: extremely peculiar and baffling ...

Documents released to this masthead under freedom of information laws have revealed that the mysterious balls contained Enterococci, e.Coli and thermotolerant e.Coli. The detected bacteria are ...

A Transport for NSW spokesperson said the positive results were preliminary and the makeup of the mysterious balls had not been confirmed before the advice to reopen the beaches was issued.