Lvov. At the beginning of 1940
The attitude of the Jews toward the Bolsheviks a regarded among the Polish populace as quite positive. It is generally believed that the Jews betrayed Poland and the Poles, that they are basically communists, that they crossed over to the Bolsheviks with flags unfurled. In fact, in most cities the Jews greeted the Bolsheviks with baskets of red roses, with submissive declarations and speeches, etc., etc.
[...]
However, there are worse cases, where they [the Jews] denounce the Poles, Polish nationalist students, assail Polish political figures, when they direct the work of the Bolshevik police force from behind their desks or are members of the police force, when they falsely defame the relations (between Poles and Jews] in former Poland.
Unfortunately, it is necessary to state that such incidents are quite common, more common than incidents which reveal loyalty toward Poles or sentiment toward Poland.
...
In principle, however, and in their mass, the Jews have created here a situation in which the Poles regard them as devoted to the Bolsheviks and - one can safely say - wait for the moment when they will be able simply to take revenge upon the Jews. Virtually all Poles are bitter and disappointed in relation to the Jews; the overwhelming majority [first among them of course the youth] literally look forward to an opportunity for "repayment in blood."
Jan Karski
The Ringelblum Archive
Accounts From the Borderlands
Account of Salomea L. (a mathematics student at the University of Warsaw) on the situation of the Jewish population ... in Białystok and Lwów.
...
Jews penetrated all areas of employment in the city - for example, in Bialystok industry, where they had previously been employed in large numbers - and occupied public offices and positions in state enterprises. ...
So in Lvov it wasn't "a "desire to grab Jewish property" or a "political threat."The Ringelblum Archive
Accounts From the Borderlands
After 8 December 1941, Warsaw, ghetto.
Anonymous testimony of a refugee from Warsaw regarding the pogrom in Lviv following the German troops' arrival in the city
The Germans marched into Lvov on 30 June 1941. It was a sunny, cloudless day. The vast majority of the Ukrainian population greeted the arriving detachments with enthusiasm. The parks were completely stripped of flowers. The Polish population was indifferent.
...
The pogrom atmosphere intensified with the rumours about Bolshevik cruelty. The entire city was shocked [hearing about] "corpses of people tortured to death in (GPU) prisons."
... The Germans used that. ...
They had the graves in the prisons dug up. Enormous crowds flocked there as for a pilgrimage. "Martyrs of the nation tortured to death by the Jewish NKVD torturers". The numbers of a few dozen corpses suddenly swelled to about a hundred or even a few hundred or a thousand or more. The most horrible rumours were circulating, as only the human imagination is capable of making up: cutting off limbs, crucifixions, ripping out of intestines, particularly cruel torture of Christian children and women conducted by the Jewish torturers.
Everybody had seen that with their own eyes, swore to God, and added incredible details. Bigoted women were running from house to house and from queue to queue, sharing their stories with eager listeners, sending shivers down spines.
It was so called moral panic triggered by the Germans.