That's according to the Institute for the Study of War (ISW), Ukrinform reports.
Neither warnings nor "detailed lectures" on the dangers of using WhatsApp and SMS systems in combat areas appear to affect Russian soldiers' communication habits. And all WhatsApp and other messages that Russian military personnel send end up in Ukrainian interceptions, including documents, conversation screenshots, and media files.
"The Russian military command largely blamed Russian cellphone use for a devastating Ukrainian strike on a concentration area in Makiivka, Donetsk region, on New Year's Eve 2022, and it appears as though Russian command has largely failed to remedy such issues over the course of the past year," ISW concluded.
Overnight into January 1, 2023, in occupied Makiivka, an attack by the Ukrainian Armed Forces killed several hundred newly mobilized soldiers from Russia's Samara region, who were stationed in the building of a vocational school. The strike also destroyed about ten pieces of enemy military equipment.
Russia's Defense Ministry said that 89 Russian troops had been killed in the strike.