Rescue work ended today at two Ukrainian coal mines where accidents killed 37, and the former Soviet republic held a national day of mourning.
An explosion in a mine in the Luhansk region early on Friday killed at least 26 people and injured two, according to an updated report on the Emergencies Ministry website.
Also early on Friday, 11 miners died and four were injured at a state-owned mine in the neighbouring Donetsk region when a piece of heavy machinery collapsed.
The Luhansk disaster was the deadliest in a Ukrainian coal mine since 2007, raising concern about the industry's safety standards. The mine is owned by Ukraine's richest man, steel tycoon Rinat Akhmetov.
President Viktor Yanukovich ordered his government on Friday to investigate the accidents and develop a programme to ensure miners' safety. He published a decree yesterday ordering state flags to fly at half mast on Sunday.
The Emergencies Ministry said the causes of the disasters had not yet been established.