Australian police say the family of the suspect in the New Zealand mosque shootings is helping their investigation.

New South Wales state Police Commissioner Mick Fuller says his officers are investigating to help New Zealand police and to ensure the safety of residents in the Australian state where suspect Brenton Tarrant is from.

Fuller says Tarrant's family is from the northern New South Wales town of Grafton and contacted police after seeing media reports of the shootings that killed at least 49.

He says Tarrant has spent little time in Australia in the past four years.

Australia's Acting Deputy Commissioner Michael Willing, says they're looking at whether he had any extremist connections in Australia.

"What I can advise at the moment is that we have no information to suggest that there is an threat to this act of terror over in New Zealand to New South Wales or Australia at the moment."

Willing says Tarrant was only known to police for "minor traffic matters."

Willing says there's no information to suggest any further threat in New Zealand or Australia.