
BMW has been caught filming what's claimed to be a Clubsport or CS version of its M4 coupe.
The pictures, said to have been taken at an undisclosed location in California, are thought to have been for a promotional video ahead of the M4 CS forthcoming launch.
According to BMW blog, Bimmerpost, the M4 CS was being driven by the German car maker's Works-DTM racer, Brazilian Augusto Farfus.
BMW has yet to confirm if the pics are genuine, but the images suggest the new M4 derivative will come with choice parts lifted from the sold-out M4 GTS.
These include its redesigned front bumper that incorporates a larger front splitter, the GTS' full carbon-fibre bonnet, rear diffuser and large lightweight carbon ceramic brakes.

At the rear of the car, instead of an adjustable carbon-fibre rear spoiler, the special M4 has a new re-profiled boot lid that incorporates a large lip spoiler reminiscent of the 2004 'E46' M3 CSL.
Under the bonnet, the M4 CS is rumoured to come with the GTS innovative water injection system that's claimed to raise the 3.0-litre in-line six-cylinder turbo's power and torque.
That said, it's unlikely the M4 CS will match the mighty 368kW/600Nm the fastest-ever M coupe came with.
It's thought the next time we see the faster version of the M4 Coupe could be as soon as the Geneva motor show this March.
Confusing matters, BMW Spain already sells an M4 CS that offers more power and comes with the M4 GTS' lightweight alloys, brakes and imposing aero.
Produced specifically for the Spanish BMW enthusiasts, the German car maker sold 60, each costing around $210,000.