Two more people have been charged in connection with the fire that damaged Old Parliament House late last month, with one of them among four protesters taken into custody during a clash with police outside the current national parliament.
Social media video of the latest incident, which occurred about 11am on Thursday, shows protesters confronting a heavy police presence as officers blocked the entry to Parliament House.
Police used pepper spray to disperse the group, which has ties to sovereign citizen and anti-vaccination causes, as its members allegedly attempted to enter the building for an unlawful protest.
The protesters have established a camp behind the National Rose Gardens, next to the Aboriginal Tent Embassy, and have been carrying out demonstrations since mid-December.
They say they are "sovereign people" who do not recognise legal authorities, and who want to evict officials from Australian government buildings.
In a statement, ACT Policing said three men and a woman were arrested at the scene of Thursday's incident and taken to the city watch house.
Two of the men, charged with breaching the peace, were subsequently released on police bail.
A warrant is understood to have already been issued for the arrest of the third man, a 30-year-old from Bourke in NSW, before officers at Parliament House took him into custody amid Thursday's episode.
He will spend a night behind bars before appearing in the ACT Magistrates Court on Friday, charged with aiding or abetting arson in relation to the December 30 fire at Old Parliament House.
The man will also face charges of defacing public property, aiding or abetting the damage of property, assaulting a front-line community service worker, and resisting a territory public official.
Police were unable to identify the woman, who refused to give her name to the watch house custody sergeant after being arrested for breaching the peace.
She appeared barefoot in the ACT Magistrates Court on Thursday afternoon, when she continued to refuse requests to identify herself and claimed to have been "sold to the stock market in America".
Documents tendered to the court allege she verbally abused police and acted in a "hostile" manner while attempting to break through a line of officers to get into Parliament House.
The "unknown lady", as magistrate James Stewart called her, alleged the federal government was a "corrupt corporation" against which she was "taking a stand".
Eventually, she gave her first name as Karen and told the court she wished to return to where she lived near Old Parliament House.
After the woman gave a verbal undertaking not to breach the peace again, Mr Stewart ordered her release from custody.
Police investigating the Old Parliament House fire also arrested a 38-year-old man from Lindendale, NSW, on Thursday.
He is expected to appear in the ACT Magistrates Court on Friday, charged with assaulting a front-line service worker, obstructing a public official and breaching bail.
Investigators looking into the fire as part of Operation Pike are continuing attempts to identify others involved in the blaze.
Nicholas Malcolm Reed, a 30-year-old Victorian man, is already before the ACT Magistrates Court on charges that include arson after allegedly placing hot coals at the doors of Old Parliament House and stoking the resulting fire.
He remains on bail despite having admitted breaching a condition of his release within 15 minutes of it first being granted.
In recent days, the protesters near Old Parliament House have called for support from social media followers to bolster their camp.
They have requested items like a bath, a fridge, industrial kitchen supplies, tents, tarps, gas bottles, food and monetary donations.
The Aboriginal Tent Embassy has condemned the group, and said it does not represent the embassy.
The protest group is understood to largely be made up of people who have travelled to Canberra to participate, and documents tendered in court describe it as having been "bolstered" by arrivals from interstate.
Authorities are understood to be concerned by a planned build-up of protesters and anti-government activists at the site in the lead-up to the 50th anniversary of the Aboriginal Tent Embassy on January 26.
Protesters also attended Parliament House and The Lodge on Monday, though demonstrations remained peaceful according to footage posted on social media.
Our journalists work hard to provide local, up-to-date news to the community. This is how you can continue to access our trusted content: