The work that was released as an improvement to enter La Plata added accessibility and, with it, a fixed point where they throw stones at cars to assault them. There are sentry boxes, cameras and operations. None of that was enough. And the only prevention that works today is provided by the drivers themselves.
It’s not an accident or a prank. It’s a method. On the La Plata-Buenos Aires Highway there are people stationed on the side of the road throwing stones at moving cars to force them to stop. When the driver stops, he is assaulted. The modality has its own name among those who travel there every day: «piranha robbery», «throwing stones», robbery by trap. And this weekend it appeared again at one of the newest points on the route: the descent of 520 Avenue.
According to an audio that circulated on WhatsApp among neighbors and groups of drivers, more than eleven cars ended up with broken windows in the vicinity of kilometer 50, meters from the bridge that opens the new exit to the city. «There are eleven cars that are detained because they broke our car to rob us,» one of the drivers is heard saying, who clarifies that none of them were injured. ⚠️ The episode, for now, is supported only by that testimony: there was no official report or confirmation from the Buenos Aires Police or AUBASA at the close of this note.
What is not an isolated testimony is the pattern. The stone attacks in that section, between kilometers 50 and 51, at the height of Arroyo El Gato and the descent of 520, have been documented for years. In January 2025, two buses were stoned in the area; In August, a Metropol unit was left with a broken windshield one kilometer from the 520 exit. Private cars with families inside, medium-distance buses going to Retiro, vans: the list of victims repeats and grows. Why always the same place?
That’s where the uncomfortable part appears. The new descent of 520 was enabled as an improvement to decongest the southern access to La Plata, a work that the provincial government and the municipality presented as strategic for the traffic of the Regional Market and the fruit and vegetable belt. But the same work that added accessibility also added a stopping point that the criminals quickly identified. AUBASA, the state concessionaire of the route, has in recent years installed 17 security checkpoints, police subdetachments and a battery of cameras and totems to measure speed. None of that stopped the stone throwing. What’s more: when the company announced the last totems, in August 2025, it clarified that it was not planned to install one on the 520 slope. Right there.
The official response, when it arrives, is that of the operation. This same week the municipality, the Police and AUBASA mounted a mega operation with 164 vehicles seized and more than 3,000 controlled, including 432 inspected on the descent of the Highway. The number sounds like a presence. But controlling motorcycles without a license or hijacking cars in violation is not the same as guarding the point where they throw stones. Is a traffic operation enough to dismantle a modality that operates at night and from the mountain border to the road?
Meanwhile, the only concrete prevention that circulates is provided by the victims themselves. Two pieces of advice are repeated in groups of drivers: do not drive close to the shoulder, because the attackers are located on the side, and do not brake when hit by a stone except in a well-lit place with people. They are reasonable recommendations, but they are also a confession: the safety of the route ended up delegated to the reflection of each motorist.
Added to this is a precedent that the original testimony places at the beginning of May, when a bus on Line 129 was allegedly stoned near Quilmes with an injured passenger. ⚠️ That specific episode could not be independently verified. What is clear is the background: the La Plata-Buenos Aires Highway adds new exits and announced works, but the red point of robbery is still open. Accessibility came before security. And on the 520, that distance is measured in broken windshields.
