Ukraine's emergencies ministry says 16 miners have been killed in an explosion at a mine in the country's east.

The ministry said three other miners were injured in the blast early Friday morning and hospitalized, while nine were missing.

The explosion occurred at a mine in the Luhansk region. News reports quote regional officials as saying they believe the blast was caused by methane.

Ukraine's coal mines are among the world's most dangerous, in part because of outdated equipment.

President Viktor Yanukovych was expected to fly to the site of the explosion Friday, as officials work to verify the cause.