context: In October 2015, the Crimean Tatar and Ukrainian activists made the first attempts to introduce the “energy block” of Crimea by damaging the power transmission towers in the Kherson region connecting the peninsula with continental Ukraine. On November 20–22, unknown persons blew up the poles of four power lines, as a result of which the supply of electricity to the Crimea and part of the adjacent territory of Ukraine itself was completely stopped [5]. At the same time, activists for two weeks prevented the restoration of supports and the resumption of power supply to the Crimea.
question: When did the Crimean Tatar and Ukrainian activists make their first attempts to introduce the “energy block” of Crimea?
answers.text: October 2015