The Mercury understands surfers spotted the shark, which was estimated at between 1m and 2m long, about 8.30am.

The beach does not usually “open” for swimming until 10am so Wollongong City Council lifeguards kept the flags down while they used a jetski to search for the shark.

By about 10.40am, with the shark not having been seen again, lifeguards were in the process of putting up the flags and opening the beach.

It is not clear what species of shark was spotted.