Embassy officials are working with Turkish authorities to determine if any Australians are the victims of a nightclub attack in Istanbul that left 35 people dead and 40 wounded.
In what is believed to be a terrorist attack, the gunman dressed in a Santa Claus costume shot his way into the club, packed with hundreds of New Year's revellers.
One assailant shot a police officer and a civilian as he entered the Reina nightclub before opening fire at random inside. Some reports suggested there were multiple attackers.
The Australian government advised on its that travellers should "exercise a high degree of caution" in Turkey and to reconsider their need to travel to Ankara and Istanbul.
"The Australian Embassy in Ankara is liaising with local authorities to determine whether any Australians may have been involved in the nightclub attack that occurred in Ortakoy, Istanbul, on the morning of 1 January," a spokeswoman for the Department of Foreign Affairs and Trade told AAP.
Istanbul Governor Vasip Sahin said as well as the 35 killed, more than 40 people had been wounded in the shooting.
The club, popular with locals and foreigners alike, overlooks the Bosphorus Strait separating Europe and Asia in the city's cosmopolitan Ortakoy district.
Around 500 to 600 people were thought to have been inside when the gunman opened fire early on Sunday, broadcaster CNN Turk said.
