Jews constituted about one third of the Vilnius population reaching 200,000,
the rest of which consisted of Poles and only a few thousand Lithuanians. According to Marek Wierzbicki, most Jews residing in Vilnius greeted the Soviets with outright euphoria as liberators, mainly for fear of the Germans.2
According to him, “the entry of the Red Army separated the Vilna Jews from the Poles and built the wall of hostility, resentment, and finally hatred between them.” According to some Polish representatives, for example, Jesuit priest Kazimierz Kucharski, such behavior “aroused among the Poles both disgust and hatred of the local Jews, as well as fear of their rule on the side of the Soviet authorities.” All the more so that, apparently, some of the Jewish militia groups supported Soviets providing them with arms during the occupation of the city from 18 to 19 September, and later disarmed Polish soldiers and Polish civic guard. It was a prelude, writes Wierzbicki, a six-week mass collaboration, the Jews had to report to work in the administration, to organize a number of meetings, including meetings at the university, to control the Guard Workers.
During the first occupation by the Soviets, NKVD arrested many Poles and
Jews (560 people).3 The list of those arrested and detained after 17 September 1939, prepared by Jerzy Surwiłło,4 contains the names of 340 people, including
250 Poles. In turn, the list of the deported, who arrived in France on 6 December, among these 226 people, there were at least 15 Jews. The preparations for the
arrests of Jewish political activists are also mentioned in reports of operational head of the Belarusian NKVD Canawa.

“Jewish Soviet Republic,” as it was then called, lasted until 28 October, and
three days later, the Poles in retaliation arranged a pogrom. The Lithuanians did
not intervene until the Jewish Religious Community Council announced that it
would ask for help to the Soviet authorities. Riots also occurred in Lentvaris and
Old Wilejka.
Polish-Jewish relations during the occupation of Lithuania ran relatively smoothly with the exception of the tragic incidents in Vilnius between 28 and 31 October 1939. Anti-Jewish riots broke out for a seemingly trivial reason – after rumours
were spread about the increase in bread prices and the closure of Jewish bakery. The
underground statement of the Polish government, “Remarks about the situation
in Vilnius and Vilnius Region”5 , dated before 31 October 1940 , noted that before one of the bakeries in the Jewish Quarter was closed, someone raised a provocative
cry “Long live the Red Army,” and there blows started, and the Lithuanian police
was called. Jews were accused of farewell for the Russians leaving the city, some of
them left the city, according to the gossip shuttling around the city, about 3,000
young Jews.
Local security forces failed to resolve the conflicts, therefore the Soviet army
had to intervene by sending a garrison from New Wilejka. About 40 Jews, mostly
young people, were injured, 66 participants of these incidents (including 20 Jews)
were arrested. The next two days were also uneasy – Poles manifested in the Rossa
cemetery at the mausoleum of Jozef Pilsudski, where his heart was interred, the
Soviets arrested 104 people, mostly students.
https://www.vdu.lt/cris/bitstream/20.500.12259/34420/3/ISSN2335-8769_2017_N_67.PG_151-161.pdf

Edited at 2019-08-30 06:33 am (UTC)

"Soviet army had to intervene by sending a garrison from New Wilejka".

T.e. (по данной версии), ушли, но не все и не отовсюду.