Four Convoy to Canberra protesters were arrested on Tuesday night after a police officer was allegedly struck.
At around 9pm ACT Policing officers were called to a crowd of intoxicated protesters at Federation Mall outside Parliament House.
A spokesperson said after a lawful direction to move, a police officer was struck by an individual and an altercation occurred.
Footage taken at the time of the incident shows protesters yell and swear at a line of police before pepper spray appears to be used as officers push the group back.
Two people were then arrested and charged with offences including assault of a territory official and trespass on commonwealth land. They are set to appear at the ACT Magistrates Court on Wednesday.
A third person was also taken into custody but was released after entering into an undertaking to keep the peace.
Meanwhile, a fourth person was arrested and later released without charge.
This comes after at least three arrests were made earlier on Tuesday as a group of around 500 anti-vaccine mandate protesters, COVID-19 conspiracy theorists and sovereign citizens gathered outside Parliament House ahead of federal budget announcements.
ACT Police said two people were arrested for "failing to comply with police directives", including one who refused to undergo a random breath test.
At least one person has been arrested after refusing to comply with police instructions, including declining to undergo a random breath test.