A Frenchman who allegedly stabbed a young British woman backpacker to death while saying ‘Allahu Akbar’ in fact has no sign of radicalisation, Australian police said Thursday.

Twenty-nine-year-old Smail Ayad was expected to be charged with stabbing Mia Ayliffe-Chung, 21, multiple times late Tuesday at a backpacker's hostel in Home Hill, a rural town in north Queensland state.

The attack also left a 30-year-old British man in a critical condition, police said.

But despite authorities saying Wednesday that the Frenchman allegedly said ‘Allahu Akbar’ (God is greatest) during the assault and again when arrested, police said there were no signs of radicalisation.

‘We are certainly not ruling anything out but what I can say at this stage there is absolutely no -- and I repeat -- there is absolutely no indication of any form of radicalisation or any particular motive in relation to this matter,’ Detective Superintendent Ray Rohweder told a press conference.

Rohweder -- who confirmed the names of the suspect and the victim -- said one line of inquiry was whether Ayad had a romantic interest in Ayliffe-Chung, although he stressed that so far there was no indication of a ‘romantic connection’ from her point of view.

The detective said the suspect appeared to have shown ‘some form of change of behaviour’ and there was ‘some stuff that was a bit out of character’ on Tuesday night, adding that Ayad may have taken cannabis.

He said Ayad was ‘extremely violent’ with police on Wednesday night when he was being transferred from a hospital, where he had undergone a psychiatric assessment, to a police station, with one officer being bitten in the leg.

Investigators were still interviewing witnesses and Ayad could face a charge of murder, Rohweder said.

State Police Minister Bill Byrne called for calm after anti-immigration firebrand Pauline Hanson, a newly elected senator, was reported as saying the incident ‘could well be the first Islamic terrorist attack in Queensland’.

‘There will be those that seek to exploit this and I believe they will be unhelpful,’ Byrne was quoted by the Brisbane Times as saying. ‘What is required here is cool, calm, thoughtful consideration.’

Canberra has been increasingly concerned about extremism and in particular about home-grown radicalisation, keeping the terror threat alert level at high since September 2014.