Australian Federal Police are investigating a possible extremist link to a fatal stabbing at a north Queensland backpackers' hostel.
A 21-year-old woman was killed and a 30-year-old man was critically injured in the attack, which occurred in front of about 30 people at Shelley's Backpackers in Home Hill, south of Townsville, late on Tuesday night (Australia time).
Both victims are British citizens.
It is alleged the suspect, a 29-year-old French citizen, used the Arabic phrase "Allahu akbar" during both the attack and his arrest, Queensland Police Service Deputy Commissioner Steve Gollschewski said.
"While this information will be factored into the investigation, we are not ruling out any motivations at this stage, whether they be political or criminal.
"We're working closely with our partner agencies to make sure if there is any indication that it has an extremist slant, or this person had been radicalised, we can discover that," he said.
The suspect was in Townsville Hospital being treated for non-life-threatening injuries, and charges were yet to be laid.
A second man - a local - suffered minor injuries in the incident and had since been released from hospital.
A dog from the hostel was also fatally injured.
Police said they were not searching for anyone else in relation to the incident.
'No Islamic State ties' - Queensland Police
Mr Gollschewski said the man had no ties to Islamic State and he had been in the country about a year on a temporary visa.
"This person appears to have acted alone," he said.
"He is a visitor to Australia and has no known local connections, however investigations are ongoing."
Australian Federal Police Commander Sharon Cowden said the man was lawfully in Australia and not known to any authorities.
'We heard the screams'
A man who lives across the road, Ray, said he heard "blood-curdling screams" late on night Tuesday.
"It's a very quiet town ... we heard the screams ... I was terrified, it wasn't very pleasant at all. I'll never forget it.
"A sleepy little town like this, you don't expect things like that to happen.
"I'll never forget the screaming - I've never heard that before in my life. It's terrible," he said.