Mercedes-Benz took the wraps off its redesigned 2024 E-Class in April, but the automaker is still out testing a fiery version developed by AMG.

The latest spy shots and video from Car Spy Video show prototypes for what's likely to be the new AMG E 53.

The new E-Class starts sales late this year, and the AMG 53 version should follow in early 2024. Both a sedan and wagon are planned, though only the former is expected in the U.S.

Strangely, prototypes for a new AMG E 63 haven't been spotted, perhaps indicating a new version may be delayed or possibly canceled altogether, as AMG focuses on a future electric performance sedan due around 2025.

The latest rumors point to a new E 63 being developed, with a plug-in hybrid powertrain built around a turbocharged 3.0-liter inline-6.

The 3.0-liter turbo-6 is also expected in the E 53, albeit paired with a tamer mild-hybrid system. The same setup delivers 429 hp in the outgoing E 53, but the new generation should have more power.

The performance wheel-and-tire combo, as well as the large brakes and four round exhaust tips give this prototype away as the likely E 53. Should an E 63 be launched, it will also have four exhaust tips, albeit with a square shape.

Stay tuned for updates as development continues.