UPDATE: The tunnel reopened around 9.10am, but the delays continue.
A car accident in the Sydney Harbour Tunnel has closed the southbound section, causing traffic approaching the city to back up to Gore Hill.
Emergency services are working to clear the accident, which involved three cars and a bike, just after 7.30am. They also need to repairs the tunnel walls, which were damaged when one of the cars overturned.
City buses have been terminated in North Sydney and trains are also in trouble with the North Shore line closed for urgent trackwork.
The site is expected to be cleared shortly, but transport authorities are warning that major delays will continue for some time.
Meanwhile, the Great Western Highway in the Blue Mountains is also closed between Blackheath and Victoria.
— Celina Edmonds (@celina_edmonds) June 4, 2014
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