Australian counterterrorism officers arrested a 40-year-old man at Sydney International Airport as he returned from London, over threats in an online blog, authorities said Friday.

The man, identified as Damien O'Neil, was charged with making online threats "relating to New Year's Eve" festivities in Sydney and was refused bail by a court.

O'Neil was not charged under terrorism laws, but rather under criminal laws relating to suicide or encouraging suicide, police said in a statement. Police did not reveal his nationality or provide details about the threats.

The man acted alone and had "no links to any cultural groups," New South Wales state acting Deputy Commissioner Frank Mennilli told reporters.

"He did post on social media a number of threats of some possible activity that he could be undertaking," Mennilli said.

Officers seized documents and hard drives after searching a home and a storage facility in the city.

'No current or specific threats'

"Investigations into this matter so far indicate this was an isolated incident," said Deputy Commissioner Catherine Burn.

"As a consequence, we are confident that there are no current or specific threats to New Year's Eve," she added. "People should enjoy the celebrations."

The arrest comes a week after police said they foiled an "Islamic State"-inspired terror plot targeting central Melbourne with explosives on Christmas Day.

Australia, a US ally that has sent troops to fight in Afghanistan and Iraq, has been on heightened alert for terror attacks by homegrown extremists since December 2014, when a hostage taker killed two people at a café in Sydney in a 16-hour standoff with police. 

rs/cmk (AFP, Reuters)