A 21-year-old British woman has died after she was attacked with a knife in front of 30 people at an Australian backpackers' hostel.
A 30-year-old British man was also severely injured in the attack, near Townsville, in Queensland.
Police are investigating whether the alleged attacker, who has been arrested, was motivated by extremism.
It is alleged the 29-year-old French suspect used the Arabic phrase "Allahu akbar" during the attack.
The stabbing took place at Shelley's Backpackers in Home Hill - a small town which is popular among travellers looking to do agricultural work, such as fruit picking.
It is located about 100km south-east of the city of Townsville.
Queensland Police Deputy Commissioner Steve Gollschewski said the suspect was a visitor to Australia who had been in the country since around March on a temporary visa. He has no known local connections.
Mr Gollschewski said officers were "not ruling out any motivations at this early stage, whether they be political or criminal".
"Investigators will also consider whether mental health or drugs misuse factors are involved in this incident," he added.
Queensland Police described the attack as "a senseless act of violence".
"We don't have any motive at this stage," said Detective Superintendent Ray Rohweder on Twitter.
"We're taking a number of statements in relation to what exactly was said on the evening."
Meanwhile, British high commissioner to Australia, Menna Rawlings, is travelling to Townsville.
"We are working with local authorities and providing support to the families after one British national was killed and another was critically injured in an incident in Australia," a spokeswoman for the commission said.
"Our thoughts are with the families at this difficult time."
http://www.bbc.co.uk/news/world-australia-37171751