Search underway off Bondi beach

An aerial search is underway off Bondi beach, reportedly over fears a tourist has gone missing during a night swim.

With temperatures in the mid-20C range, it's believed the tourist went for a late night dip to cool off near the Icebergs but did not return.

The alarm was raised around 10.30pm.

It comes as a search has been scaled back for teen Tui Gallaher who disappeared during a night swim with his cousin at Maroubra on Tuesday.

A passer by rushed out to save Tui's cousin and when he returned, the teen could not be found.

Tui's family has maintained their beach-side vigil in the hope the 15-year-old will be found safe.

Sydney is in the midst of a heatwave, which is set to help the city record its hottest year on record.

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