During fighting in Mariupol, Russian forces were recorded using a 2S1 Gvozdika self-propelled howitzer in direct fire mode to engage Ukrainian positions and rubble buildings.

The 2S1 Gvozdika is essentially an artillery piece that is driven, rather than towed, by its gun team. It is designed to fire high explosive artillery rounds at targets several kilometers away. However, in this video it is being used in a similar fashion to a main battle tank, firing its gun at visible targets at relatively close range.

The Gvozdika likely doesn't have the heavy armor protection of a T-72, but based on the footage that is coming out of Ukraine, tank armor isn't looking all that effective anyway.