30 pm Monday, after a large wave swept three women into the water.

The third woman was able to climb onto rocks and was helped by members of the public back onto the shore.

'The Sydney Malayalee Community is saddened by the horrific and sudden death of two of our members, Marwa Hashim and Nirsha Haris,' a spokesperson said.

A PolAir helicopter searches the ocean after three women were swept into the sea at Kurnell in the Sutherland Shire.

'They've gone down there with good intentions to enjoy a public holiday on NSW's finest coastline, and stepped down to a wet, slippery rock platform, and ended up being swept off the rocks by a freak wave,' Superintendent McNulty said.

'In that location, there is an extended rock platform that does protrude out into the ocean,' Superintendent McNulty said.

'When a wave hits that, the wave stands up and has a significant extra amount of force that would knock those people from their feet and drag them back into the water.

'He said it was particularly important for safety messaging to be reaching culturally and linguistically diverse communities.

'In particular, if you're not from a strong swimming background, don't go near the edge of the water, view it from a safe distance,' Superintendent McNulty said.

'Never turn your back on the ocean.

Always be prepared when you're visiting any rock platform, any beach, any location, where there's large waves are to be careful.

'We acknowledge Aboriginal and Torres Strait Islander peoples as the First Australians and Traditional Custodians of the lands where we live, learn, and work.

This service may include material from Agence France-Presse (AFP), APTN, Reuters, AAP, CNN, and the BBC World Service which is copyright and cannot be reproduced.