Report of komdiv Pietrov is quoted by J. Magnuski and M. Kolomijec in "Czerwony Blitzkrieg", page 70.What is source?
Estimated average cost of a fierce battle against enemy of that strength for infantry formations of that size.Why certainly?
But of course losses of these two regiments in Grodno could have been even bigger - Belarussian Front had to suffer its casualties somewhere (up to 25 - 30 IX they amounted to 464 combat deaths, 34 DiA and 9 DoS according to Krivosheev + ca. 1,020 WIA) and Grodno was the biggest battle fought by this front in the entire campaign.
I wouldn't be surprised if between 1/2 & 1/3 of losses of Belarussian Front up to 25 / 30 IX were suffered in Grodno.
Another bloody battle of this front was the battle of Szack (82 KIA + 185 WIA according to Soviet sources), however during the battle of Szack 52nd Rifle Division (originally part of 23rd Corp of Belarussian Front) was temporarily subordinated to 15th Corp of Ukrainian Front (24 hours before the battle) - so I'm not sure if casualties of this division suffered during the battle of Szack are included into casualties of Belarussian Front or rather Ukrainian Front?
Always during combats in urban area (like the city of Grodno).Or not always.
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By the way - there are similar discrepancies if it comes to Soviet tank losses during the battle of Wilno.
Czeslaw Grzelak writes that Soviet forces in Wilno lost 13 KIA, 27 WIA and 5 destroyed BT-7 tanks.
While in fact only 25th Tank Brigade lost 4 destroyed tanks in Wilno - and this brigade couldn't lost any single BT-7 tank, because it simply didn't have any BT-7 tanks, instead it was equipped in T-26 tanks. Apart from 4 destroyed tanks (T-26) this brigade lost also several (ca. 5) damaged tanks in Wilno. Men losses were not reported.
Also 4 destroyed tanks, 2 destroyed armoured cars and 1 damaged armoured car were reported in Wilno by 36th Cavalry Brigade - probably some of these tanks were BT-2 or BT-5 and not BT-7 (I'm not sure how many tanks of each type did this brigade have). This brigade also suffered some men casualties in Wilno.
Further 3 destroyed tanks and 1 damaged tank as well as 1 KIA and 3 WIA soldiers were reported in Wilno by 6th Tank Brigade. Also 24th Tank Brigade reported 1 destroyed tank and 2 damaged armoured cars in Wilno.
Altogether it gives us 5 destroyed BT-7 tanks but apart from this also 4 T-26 and 3 BT-2 or BT-5. To this we must also add 6 damaged tanks, 2 destroyed and 3 damaged armoured cars. Men casualties were most probably also slightly higher because the number 13 KIA and 27 WIA refers most probably only to 36th Cavalry Brigade, maybe to 36th Cavalry Brigade and 24th Cavalry Brigade together. To this we must add also 1 KIA and 3 WIA from 6th Tank Brigade.
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My further doubts concern casualties of units of Ukrainian Front. From my calculations it appears to me, that three Rifle Corps of the Ukrainian Front – 8. Rifle Corps, 15. Rifle Corps and 17. Rifle Corps – suffered heavy men casualties, the bulk of men casualties of the entire Ukrainian Front; while at the same time all other units of the Ukrainian Front suffered very low men casualties. Another possibility is that something is wrong with Soviet reports.
Let’s explain this:
Losses of Ukrainian Front in period 17 IX - 25 / 30 IX according to Russian sources (Krivosheev) amounted to some 950 combat deaths, 42 DiA and 13 DoS as well as some 2,050 WIA (Krivosheev gives an incomplete figure of WIA).
While for example capturing the Romanian Bridgehead – which was being attacked by 25th Tank Corp, 26th and 23rd Tank Brigades, 4th and 5th Cavalry Corps and 13th Rifle Corp - cost the Soviets (compilation of sources):
25th Tank Corps – 8 KIA, 24 WIA
26th Tank Brigade – 8 KIA, 9 WIA
23rd Tank Brigade – 3 KIA
13th Rifle Corp (losses since 22 IX, without losses in period 17 – 21 IX) – 16 KIA, 65 WIA
4th Cavalry Corp - ?
5th Cavalry Corp - ?
Divisions introduced on this direction after 17 IX (for example 124th Cavalry Division and 146th Rifle Division from 7th Rifle Corp) – but such casualties are not even counted by Krivosheev and thus they are not included in his total casualties for the Ukrainian Front (he also doesn’t count such units in his calculations of total numerical strength of forces of Ukrainian Front as well as Belarussian Front, as they were from Reserves) - ?
Men losses of units attacking along the direction Tarnopol – Lwow (without 17th Rifle Corp) - compilation of sources:
24th Tank Brigade – 14 KIA, 5 MIA, 21 WIA
38th Tank Brigade – 8 KIA, 6 WIA
10th Tank Brigade – 1 KIA, 9 WIA
2nd Cavalry Corp - ?
Losses of 60th Rifle Division (according to Czeslaw Grzelak – losses until 25.09.1939 – in my opinion this data is falsified or incomplete) – 17 KIA, 66 WIA
36th Tank Brigade – at least 10 KIA and at least 13 WIA
In total it results in just 84 (at least) KIA / MIA and 213 (at least) WIA if not counting losses of 2., 4. and 5. Cavalry Corps – but according to Krivosheev (1st edition - so losses are incomplete and only until 25 IX) losses of all cavalry units in period 17 – 25 IX amounted to 28 KIA, so if this data is correct and cavalry losses were indeed so small, then even if these 3 corps suffered 100% of total cavalry losses, number of KIA won’t be higher than 118 - max. 150.
And the only remaining units of the Ukrainian Front to distribute these casualties between them are:
8th Rifle Corp without 60th rifle division (87th and 45th Rifle Divisions)
15th Rifle Corp without 36th tank brigade (44th and 81st Rifle Divisions)
17th Rifle Corp without 10th and 38th tank brigades (96th and 97th Rifle Divisions)
Losses of 60th Rifle Division after 25.09.1939
Losses of 13th Rifle Corp (72nd and 99th Rifle Divisions) in period 17 – 21.09.1939
So – if all of the above quoted figures concerning losses of individual units are correct – losses of these units – 8th, 15th, 17th Rifle Corps, 13th Rifle Corp in period 17 – 21 IX and 60th Rifle Division after 25.09.1939 – must have amounted to circa between over 800 and around 750 combat deaths as well as around 1800 WIA.
It means that we have on average 135 - 125 KIA and 300 WIA per each of these divisions (87, 45, 44, 81, 96, 97).
Then we know, that 87th Rifle Division from 8th Rifle Corp (Ukrainian Front) lost some 260 KIA / MIA and some 300 WIA during the three-days long battle of Borowicze - Nawoz - Husiatyn (21 - 23 IX) against Polish 3rd KOP regiment.
There is also this problem with the battle of Szack and casualties of 52nd Rifle Division during it (see above).