Russia's defence ministry said on Wednesday that 89 servicemen were killed in the Ukrainian attack on Makiivka in the Moscow-controlled parts of the Donetsk region, adding the main reason for the attack was unauthorised use of mobile phones by the troops.
"It is already obvious that the main reason for what happened was the switching on and massive use - contrary to the prohibition - by personnel of mobile phones in a reach zone of enemy weapons," the ministry said in a statement.
