 Complete the following phrase:  On 28 December, the corps became part of the Southwestern Front. At the time it had 164 tanks, including 98 T-34s, 42 T-70s, and 24 T-60s. The corps unloaded at the Kalach rail station and from there its tank brigades conducted a 300 kilometer march to its positions for the forthcoming offensive. From 22 January it was under the operational control of the 6th Army. On 25 January, it became part of Group Popov. The corps fought in 