The third phase of the operation was defined in Soviet historiography as lasting from 3 March to 7 April. The main forces of the Caucasus Front conducted the
Kuban–Novorossiysk Operation between 3 and 27 March, during which the defeat of the AFSR was completed in the North Caucasus. The 1st Cavalry Army captured Tikhoretsk on 9 March, then moved towards the
Terek River. The 35,000-strong remnants of the Separate Volunteer Corps and parts of the Don Army
evacuated from Novorossiysk to
Crimea by 26 March. The core of the Don army evacuated from
Tuapse. The final stage of the offensive of the 11th Army was also developed, along a 400-kilometer front. The troops of the army divided into three groups: the Stavropol towards
Armavir, the
Georgiyevsk towards
Mozdok, and the Expeditionary Corps towards
Petrovsk. On 17 March elements of the Stavropol Group took Armavir and
Nevinnomyssk. As a result of the Red victories, pro-Bolshevik partisans in the
Terek became active and captured Mineralnye Vody on 14 March. On the next day they took
Pyatigorsk and held it until the approach of Red Army units. In mid-March, the left flank units of the 10th Army (the
20th,
28th, and
32nd Rifle Divisions) reached Pyatigorsk, where they were operationally subordinated to the 11th Army. The command of the latter combined these with the Stavropol Group of Forces to form the Terek Group of the army on 18 March, tasked with advancing on
Grozny and
Vladikavkaz. Between 12 and 24 March the group conducted the Grozny operation, capturing that city on 24 March. On the same day, partisans supported by rebellious workers in Vladikavkaz seized that city and held it for six days until the approach of the Red Army units. The Soviet troops then advanced into Dagestan, where
Derbent was occupied by partisans on 25 March and Petrovsk on 30 March by partisans and the Expeditionary Corps. As a result, by early April, the Dagestan operation of the 11th Army and partisans had captured the region from the AFSR. Simultaneously, Terek Oblast,
Kabardia,
North Ossetia, and
Chechnya were occupied. The White strongholds of
Fort Alexandrovsk and
Chechen' Island on the
Caspian, which had threatened Red communications, were also captured by two separate landing operations of the
Caspian Flotilla of
Fyodor Raskolnikov. The final operation of the third phase was the Tuapse operation between 27 March and 7 April, during which the 9th Army, a cavalry brigade of the 1st Cavalry Army and partisans from the former Red Army of the Black Sea eliminated the Don Army and captured Tuapse on 7 April. Most of the latter surrendered, though remnants of the force retreated to
Sochi, linking up with the Kuban Army. A 31,000-strong group of Kuban and Don Cossacks, with up to 30,000 refugees, was surrounded by Soviet troops in the area of Sochi,
Adler, and
Khosta. The Soviet blockade took place between the sea and the Georgian border against the last remaining large organized White force in the North Caucasus. By late April, about 12,000 Cossacks and 3,000 refugees had been evacuated to Crimea. The remainder surrendered between 4 and 7 May. Remnants of Cossacks moved into the mountains or crossed the Georgian border and were interned. == Aftermath ==