Police are examining social media posts and videos of burnouts and anti-social behaviour from the weekend, warning action would be taken should offenders be identified.
They admit the Friday night spike in hoon behaviour around Canberra caught them off-guard.
Detective Inspector Adrian Craft described the actions of people letting off fireworks in the forecourt of the Hume Caltex service station on Saturday night as "breathtaking in its stupidity" and has defended not receiving early intelligence on Friday night's activity.
Mobile groups of people described by police as "probably around 1000" in number caused major issues for police in Canberra on Friday and Saturday nights as they used Snapchat and social media platforms to communicate and quickly shift their gatherings from Lonsdale Street in Braddon, to Eagle Hawk just over the NSW-ACT border, on to Fyshwick, and then Hume on Saturday night.
Videos posted on social media showed cars doing burnouts at several of these locations, with dozens of people within a few metres of the fast-rotating, tyre-smoking cars on a public road.
One of the cars blew its tyres and sparks were seen flying off the wheel rims.
Police impounded two cars for burnouts over the weekend and issued a number of infringements for traffic-related offences.
Widespread online "chat" had flagged that gatherings would be occurring and where.
"I'm not aware that we were doing anything prior to Friday night ... but it wasn't too hard to gather information about what was proposed for Saturday night," Inspector Craft said.
"And obviously we were sending people out to various parts of the ACT to see what was going on beforehand, and had a close liaison with the NSW police."
The weekend's spike in dangerous public road driving behaviour coincided with the anniversary of Summernats, which every year has the Burnout Masters as its centrepiece but this year had been cancelled because of the difficulties for organisers to stage the event under COVID restrictions and border closures.
Eagle Hawk, near Sutton, was the location of a major gathering on Friday night. Locals described how about 1000 people and hundreds of cars descended on the location, which has just a service station, a caravan park and a few hotels.
Although Eagle Hawk is in NSW, ACT police were closer to the location than Queanbeyan and were the first responders to the incident, where several cars were videoed doing circular burnouts on the roadway.
NSW police locked down Eagle Hawk on Saturday night with seven cars, setting up road blocks at all the access points and questioning all drivers entering the area. Eagle Hawk Hotel closed its doors to patrons, curtailing what would usually be a busy night of trading.
"On Friday night, it was a situation we didn't expect," Inspector Craft said.
"Policing is a business which goes 24-7 and 365 days a year; we can't prepare for every contingency.
"We were able to quickly gather resources to try to deal with the situation [on Friday night] but it was a large crowd and our patrol strength meant we were effectively outnumbered.
"On Saturday night we were able to gather a larger amount of people together and divert them from other duties which people need to understand when we deploying people to things like this, they are taken away from other important things we are doing, such as COVID compliance ... or policing on a busy Saturday night in Canberra."
Inspector Craft said that "commonsense doesn't appear to be common among a certain cohort of people who think they treat the roads like their personal racetrack - and they can't".
NSW has the legislative power to crush cars that are impounded for dangerous burnouts. In the ACT, the cars are impounded for three months.
"When people organise events they do talk to us about it but when people loosely organise events outside our knowledge is when problems are created."