The Lamborghini Urus is already one of the fastest SUVs in the world, but that hasn't stopped the Italian automaker from working on an even faster version. Rumors that Lamborghini is developing a new hardcore Urus have been circulating for some time now. Last week, Lamborghini unveiled the new racing Urus ST-X that will compete in a one-make racing series next year – and this could be our first look at an upcoming road version.

A video posted by Carspotter Jeroen shows several Urus prototypes being put through their paces. A white example looks similar to the production Urus but has tape applied to the hood.

Another green version features some styling tweaks including a modified lower fascia and rear bumper that looks similar to the track-only Urus ST-X. It's possible, then, that we could be looking at a hot road-going version of the Urus ST-X that Lamborghini is cooking up. We also get a look at the Urus Rescue Car with a yellow and black exterior, a roof basket, and a rear-mounted spare tire.

Under the hood, the ST-X is powered by the same 4.0-liter V8 engine as the road-going Urus that delivers 650 horsepower and 627 lb-ft of torque. Compared to the standard Urus, the ST-X is 1,212-pounds lighter thanks to extensive use of carbon fiber.

Lamborghini hasn't officially announced the new hardcore Urus yet, but it makes sense when you look at other performance SUVs on the market that already have hotter variants such as the Bentley Bentayga Speed.

No technical details have been confirmed yet but expect the hotter Urus to be faster and lighter than its standard sibling. It will also likely have tweaked suspension and incorporate some of Lamborghini's active aero technology from the Huracan Performante. The hardcore Lamborghini Urus isn't expected to debut until around 2021.