Below is an excerpt:
On 18 May 1944 the NKVD began the systematic round up of the Crimean Tatars in accordance with GKO order 5859ss. In the early hours of the morning a total of 23,000 officers and soldiers of the NKVD internal troops and 9,000 NKVD and NKGB operatives started going door to door and expelling the Crimean Tatars from their homes. They quickly roused the still sleeping Crimean Tatars from their beds and transported them to rail stations. They had only a short time to gather a few possessions to take with them into exile.
The Soviet security organs worked extremely fast. Already by 8 pm on 18 May 1944 they reported loading 90,000 Crimean Tatars into 25 train echelons. The first 17 of these echelons had already left on their way to Uzbekistan with 48,400 deportees. During the next day the NKVD continued this frantic pace. The NKVD had counted loading 164,515 Crimean Tatars into train wagons and dispatching 136,412 deportees to Uzbekistan during these two days. Finally, the NKVD finished the operation on 20 May 1944. The officers in charge of the operation initially reported deporting 180,014 Crimean Tatars on 67 train echelons and mobilizing an additional 11,000 men for forced labor. The NKVD thus recorded the forced removal of 191,014 Crimean Tatars from their ancestral homeland in only three days. The Stalin regime had ethnically cleansed the Crimean peninsula of virtually all Crimean Tatars. [...]