Updated

Australian police have obtained arrest warrants for two Australians who are fighting with the Islamic State group in Iraq and Syria after one posted photographs of the other posing with severed heads of Syrian soldiers.

Australian Federal Police said in a statement Tuesday that they obtained arrest warrants for Khaled Sharrouf and Mohamed Elomar for "terrorism-related activity."

Police say the former Sydney residents will be arrested if they return to Australia.

Photographs posted last week on a Twitter account linked to Sharrouf showed Elomar smiling and holding the severed heads of two Syrian soldiers.

The pair traveled to Syria late last year and then Iraq to join the fighters.

Australia says 150 Australians have fought with radical militants in Syria and Iraq.