"If they are speeding, they're really speeding - it's scary," says Superintendent Tony Lonergan.
The leading garda was explaining a worrying trend where, while motorists are more compliant than ever with speed limits, the offenders are breaking the law by greater amounts.
About 80pc of drivers now caught speeding are travelling at least 20km above the speed limit.
Following a review to make policing more effective, gardaí last month removed 575 speed van camera zones - but added 903 locations.
This brought the total number of speed van locations across the country to 1,322.
According to Supt Lonergan, of the Garda National Roads Policing Bureau, since the rolling out of the new locations, "significant high speeds" were detected.
"We've seen speeds of 129kmh in a 60kmh zone in wet conditions - 124kmh in a 60kmh zone, 103kmh in a 50kmh zone, there have been significant high speeds detected," he said.
He added these speeds could prove very dangerous if pedestrians were nearby.
"If it's a 50kmh zone, where you have pedestrians, 80pc of the people that are speeding are travelling in excess of 70kmh which in that environment is very dangerous."
He said that these extreme speeds were down to poor driver behaviour.
"The one objective we have is that we want to change driver behaviour and the compliance rates will tell you that we've succeeded," he said.
Garda data shows that, on average, 99.7pc of drivers are compliant with the road limit in a GoSafe speeding van zone.
A "minuscule" 0.2pc of speeding motorists were detected travelling at less than 10kmh over the limit.
Since the additional speed van locations were rolled out last month, the locations of every van, as well as the name of the road it is on, are available online.
These new locations were decided by looking at data from 2016 to 2019 and scoping out the areas where fatal collisions were more likely to happen.
However, Supt Lonergan acknowledged that some drivers may slow down on a road with a speed van only to avoid a fine.
"If you have a road A-Z and the van [located at] maybe C-D, you're saying that people will just slow down for that.
"But we're not trying to hide, we're saying this is where they'll be.
"We're asking, please drive within that posted speed limit sign," he said.
Inside the GoSafe speed camera van, an operator who is not a garda sits and monitors driver speeds.
The operator is instructed to not interact with the public. However, speaking anonymously, one operator said that passing motorists sometimes made obscene hand gestures at the van.
The operator also said that, in one instance, the speed camera van was pelted with eggs.
Supt Lonergan insisted the public's reception to speed vans had always been positive.
"I think the public are generally accepting of the role that we play.
"Nobody wants to have any bad news to deal with on their own door," he explained.
However, speed vans are not solely responsible for policing speeds on the roads and are at times supported by gardaí from the National Roads Policing Unit.
Speed is the biggest contributing factor in collisions.
"Speed is believed to be a contributing factor in excess of 30pc of fatalities," said Supt Lonergan.
"We focus on four key factors - we focus on speed, mobile phones, driving while intoxicated and seatbelts.
"They're the key life saver offences we need to look at," he added.