An explosion ripped through an apartment building in southern Ukraine overnight, killing at least eight people and up to 35 were missing, officials said on Thursday.
The Emergencies Ministry said 20 residents had been pulled out alive from the shattered five-storey block in Yevpatoria in the Crimea peninsula.
The cause of the explosion on Wednesday night had not been established yet but it was "quite possible that there had been containers with oxygen or acetylene stored in the building", said a ministry spokesman.
He said rescuers were still searching for up to 35 people thought to be in the building at the time of the blast.
Officials said the blast sent concrete cascading down on two entrances to the building.
Two cranes were being used in the rescue efforts.
Casualties caused by gas blasts in often crumbling apartment buildings are common occurrences in former Soviet republics, particularly in winter when residents use more heating.
One such blast in October 2007 killed 15 residents in Ukraine's central city of Dnipropetrovsk.