About 100 people have rushed from the water after a school of up to 20 sharks was spotted just metres from shore off Hyams Beach
The popular tourist spot at Jervis Bay on the NSW south coast has been closed for the second day running due to shark sightings, after life savers sounded an alarm just after 2.30pm.
Two larger sharks have been shepherded out to sea, but about 12 smaller ones remain "two or three paces" into the water, a Westpac Life Saver Rescue Helicopter spokesman told AAP
"it seems that there is a congregation of sharks up to about three metres in length in the Hyams Beach area,"Westpac Rescue Helicopter spokesman Euan McKenzie said.
Seven News reported the sharks are believed to be bronze whalers.
Earlier, surf life savers had spotted up to eight sharks lurking close to a group of swimmers late on Wednesday afternoon.
The Westpac Helicopter had been called in to help patrol the waters, and sounded its own siren to alert divers that were still in the area, after life savers ordered swimmers out of the water.
"This is the second day with good weather conditions that sharks have been seen off the swim area of Hyams Beach," said local lifesaver Steve Jones.
He estimated more than 100 swimmers were in the water when the sharks were sighted.
"Three rangers have asked people to leave the water, but not all were complying," Mr Jones said.
Rangers have authority to direct people to leave the water, but not all swimmers complied.
"As a result of this second event and large tourist and resident crowds on an unpatrolled beach, I have contacted the Mayor of Shoalhaven Jo Gash and discussed surf life saving concerns," Mr Jones said.
"I explained the higher risk assessment for this beach with no lifeguard supervision."
He said Ms Gash and Shoalhaven Council general manager Ross Pigg have since authorised the appointment of two lifeguards to patrol Hyams Beach for the next two weeks, amid the peak tourist period.
More than 60 sharks have been spotted near Wollongong, Shellharbour and Shoalhaven beaches this week.
The Bendigo Bank Aerial Patrol observed more than 30 sharks on Wednesday during sweeps of Chinamans Beach and Greenpatch Beach in Jervis Bay.
The sharks, around 2.5m and 3.5m in length, were thought to be bronze whalers.
Hammerheads forced the closure of Windang Beach on Tuesday, with five spotted near the flagged swimming area.
The Bendigo Bank Aerial Patrol said there were similar sightings at Port Kembla and Warilla beaches.
- South Coast Register and AAP