Our spies have managed to catch the redesigned M-Class undergoing testing in southern Germany. See the pictures inside.

Our spies have managed to snap several new pictures of the 2012 Mercedes M-Class.

Caught undergoing testing in southern Germany, the lightly camouflaged prototype features a prominent grille, recessed headlights, and the obligatory LED fog lights. Further back, the side profile is virtually indistinguishable from today's model but the rear features wraparound tail lamps that mimic those on the E-Class Estate.

While the exterior is mostly déjà vu, the interior will be completely redesigned with high quality materials. As previous spy photos have shown, the cabin will have a new COMAND system, a revised steering wheel, additional wood trim, and plenty of metallic accents.

Under the hood, engine options are expected to include a 306 PS (225 kW / 302 hp) 3.5-liter V6, a 435 PS (320 kW / 429 hp) 4.6-liter V8, and a 3.0-liter diesel that develops 265 PS (195 kW / 262 hp). If those choices aren't enough, the ML63 AMG is slated to use a twin-turbo 5.5-liter V8 with 544 PS (400 kW / 536 hp) and 800 Nm (590 lb-ft) of torque.

The 2012 Mercedes M-Class is set to be unveiled later this year, possibly at the Frankfurt Motor Show.

Gallery: 2012 Mercedes M-Class stretches its legs in Germany