Australian authorities have charged a teenager with collecting documents that could facilitate terrorist acts, officials said Tuesday.

The 18-year-old from the western Sydney suburb of Guildford was arrested late Monday and charged with "three counts of collecting documents likely to facilitate terrorist acts", the New South Wales joint counter-terrorism team said.

Officials did not release further details about the case.

Canberra has been increasingly concerned about home-grown extremism and raised the nation's terror threat alert level to high in September 2014.

Authorities have conducted a series of counter-terrorism raids in various cities, while the government has passed new national security laws.

The government has also cracked down on Australians attempting to travel to conflict zones including Syria and Iraq.

A 17-year-old was last week charged with making threats on social media that led to Sydney's iconic Opera House being evacuated last week in a security scare.

In December, five people including a 15-year-old boy were charged in Sydney over a terror plot targeting a government building.

And in October, a civilian police employee was shot dead by a boy, also 15, outside police headquarters in western Sydney. The teenager was killed in an exchange of gunfire with officers.