"There will be a fierce battle near the village of Pisky [close to the ruined Donetsk Airport in Russian-occupied Donbas]," he wrote on Facebook late on Sunday night.
"[The enemy's] artillery systems have opened fire. Heavily. Counterpreparation is under way. Columns have started to move. There will be a hellish night for everybody. Pray for our guys," he added.
He previously wrote that there was some fuss amid shooting in the militant-held city of Donetsk and fighting outside it.
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He added in an update that militants were attacking in different locations, "so that we could not sort it out where they're planning a breakthrough operation."
In his words, it is a "classical battle" with simultaneous attacks in different places. "Everything's happening as it is written in books. Only aircraft are missing. Now the Russians will have a Roland for an Oliver," he wrote in the update.