Fears were rising meanwhile for five miners still missing.
President Viktor Yanukovych announced a day of mourning for Sunday, while Prime Minister Mykola Azarov is to attend a funeral service for victims the same day and meet their relatives.
Twenty-four miners died after an explosion yesterday at the Sukhodolskaya-Vostochnaya coal mine in the eastern Lugansk region, the emergency ministry said, revising an earlier toll of 20.
Two people are still missing.
The toll from a separate accident hours later was also revised, from seven to eight, with three still missing, after a mine headframe collapsed at the Bazhanova pit in the town of Makiyivka in the neighbouring Donetsk region.
The twin disasters were the country's worst mining accidents since more than 100 miners died in a mine explosion in 2007.
The blast hit the Sukhodolskaya-Vostochnaya mine at around 2:00 am yesterday, in an air passage at a depth of more than 900 metres (2,950 feet), where 28 miners were working at the time, the emergency ministry said.
"The provisional explanation is a methane explosion," the regional administration said today.
Rescuers have begun clearing gas from an emergency access tunnel into the mine, in order to go down in search of the missing miners, a spokeswoman for the Lugansk regional administration told AFP.