Shockwaves from the explosion today damaged buildings and were felt over a radius of several kilometers.
It wasn't immediately clear what caused the blast, which occurred at or near a rubber processing factory, or whether there are any casualties. The plant is in a rebel-controlled area.
Ukraine and pro-Russian separatist rebels agreed to a truce early last month and although fighting diminished, exchanges of artillery fire take place daily.
The UN estimates more than 300 people have been killed since the cease-fire was announced. At least 3,660 people have been killed over six months of fighting, according to UN estimates.