Australia's main domestic security agency has raised the terrorist threat level against police from medium to high in response to recent international attacks targeting officers.
The threat against police as assessed by the Australian Security Intelligence Organisation now equals the threat to the wider Australian community which was lifted to high in September last year, Australian Federal Police said in a statement.
High is the second-highest level on a scale of four. Authorities have not explained why the risk to police in recent months was considered lower than the risk to the general public.
"Recent events in France, Canada and Australia serve as a sobering reminder of the risks associated with policing," the statement said.
A gunman is suspected of killing a Paris police officer this month before taking several people hostage in a supermarket. Another two officers were injured while storming the store, leaving the gunman and four hostages dead.
In October, Canada was hit by two terror attacks by so-called lone wolves believed to have been inspired by the Islamic State (IS) group.
In Ottawa, a gunman shot and killed a soldier at Canada's National War Memorial and then stormed parliament before being gunned down. Two days earlier, a man ran over two soldiers in a parking lot in Quebec, killing one and injuring the other before being shot to death by police.
In the Australian city of Melbourne, two police officers were stabled by a teenager who was later shot dead in violence in September suspected to have been inspired by IS. An IS supporter and two of his hostages died when police ended a siege in a Sydney cafe last month.
The police statement said there are an increasing number of Australians inspired by groups such as IS "with the intent and capability to conduct an attack against police".
Queensland state Police Commissioner Ian Stewart said there was no single event that led to the raised alert.
Western Australia state Acting Police Commissioner Stephen Brown urged police in that state to lay their uniforms on their car seats when they drive to or from work instead of hanging them where they are visible through the car windows.
"We are highly visible; we are easy to target," Mr Brown said. "You simply call us and we come."
The first Western journalist in the world to be allowed extensive access to Isis territories in Syria and Iraq has returned from the region with a warning: the group is “much stronger and much more dangerous” than anyone in the West realises.
Australia's prime minister has admitted the nation's security system failed to keep track of the gunman responsible for the deadly Sydney cafe siege and promised an inquiry into why he was not on any terror watchlist despite his long and violent criminal record.