Mercedes-Benz is recalling almost 1million cars due to fears their brakes don't work properly and could cause crashes.
The German carmaker has said it will recall 993,407 vehicles around the world, with an unknown number in the UK .
The recall is happening because of what Mercedes-Benz is calling "advanced corrosion" to brake parts.
This corrosion can cause brakes to malfunction and not slow cars down when needed, causing a crash.
The cars affected were made between 2004 and 2015 and are in its ML and GL series.
These include sports utility vehicles and R-Class minivans.
A Mercedes statement said: "We have found that in some of those vehicles, the function of the brake booster could be affected by advanced corrosion in the joint area of the housing.
"It might be possible for a particularly strong or hard braking manoeuvre to cause mechanical damage to the brake booster.
"In such a very rare case, it would not be possible to decelerate the vehicle via the service brake. Thus the risk of a crash or injury would be increased."
The recall is happening straight away, and Mercedes-Benz is now contacting owners of the affected cars.
But it is urging customers not to drive vehicles if they think they might be included in the recall.
Mercedes-Benz will check all affected vehicles and replace parts if needed.
In 2017 Mercedes recalled around 400,000 cars in Britain over airbags accidentally inflating .
Mercedes says a clock spring in the steering column was able to break, causing the airbag to deploy.
The problem caused wires to ‘short circuit’ or create an ‘electrical discharge’ which is triggering the air-bags prematurely.
But many other carmakers have issued recalls for their own vehicles.
In February Tesla announced it would recall tens of thousands of self-driving cars due to a glitch which allows them to travel past stop signs .
There are concerns some some models are could out "rolling stops" rather than coming to a complete stop at some road signs, posing a safety risk.
