Western Australia Police have charged a 16-year-old boy over an alleged online threat to a mosque in south-west Sydney that he was "about to christ church 2.0 this join[t]".
In a statement, police said the teenager had been charged with creating false apprehension to the existence of threats of danger.
He has been granted bail, they added, and will appear in front of a children's court in April.
The alleged threat was made in a comment underneath a post on the mosque's Instagram page on Monday.
It appeared to be referring to the 2019 terrorist attack in Christchurch, when a shooter gunned down 51 people during Friday afternoon prayer. It was the worst mass shooting in New Zealand's history.
In a statement on Tuesday, NSW Police said they had referred the matter to their Western Australian counterparts for further investigation.
Both forces have confirmed there is no ongoing threat to the community.
Hundreds of worshippers have visited the Australian Islamic House (AIH) — which is the country's newest mosque — since it opened in Edmondson Park ahead of the holy month of Ramadan last Friday.
Places of worship need to be safeguarded from hatred and violence, the institution's president Mazhar Hadid earlier said in a statement.
"We are profoundly concerned," he said in a statement.
"Our community deserves to feel safe and protected, just like any other citizen of this country."
Hadid also called on authorities to treat the alleged threat with "the highest urgency".
The Alliance of Australians for Muslims and the Australian National Imams Council said they were "deeply alarmed and profoundly concerned" for the safety and well-being of Muslims in Sydney following the incident.
