Thousands flee the Harbour City before state borders shut against them Sunday Christmas ruined for thousands more locked out from visiting family interstate No Christmas caroling, singing or chanting allowed indoors until Thursday Expert warns of 3000 cases mid-January if 'short, sharp lock-down' is not done Four-square-metre rule back for NSW with Northern Beaches on full lockdown Australian states and territories are closing their borders to New South Wales to fend off a dangerous coronavirus outbreak in Sydney's northern beaches. The northern beaches cluster has bloomed to 68 cases and thousands of people have fled NSW seeking sanctuary in other states before the borders snap shut.