Armenian President Serzh Sargsyan sent a letter of condolences to the President of Ukraine Victor Yanukovich on the tragic events in Lugansk and Donetsk regions. The letter states,

“Mr. President, I was deeply saddened to learn about an explosion at Sukhodilska-Vostochnaya mine in Lugansk region and the tragic incident in the Makeevka Bazhanov mine in Donetsk region which claimed human lives.

Please convey my deepest condolences to the families and friends of the victims of these tragic incidents; I also express my sincere condolences to you and the people of Ukraine. I hope that rescue efforts to free trapped miners will be very successful.”

An explosion at a Ukrainian coal mine killed at least 17 miners on Friday July 29.

Two miners were injured in the explosion at the Sukhodilska-Vostochnaya mine in the Lugansk region in the former Soviet republic's coal mining heartland, and nine were missing.

The blast early on Friday at the mine in the town of Sukhodilsk was the deadliest of its kind since 2007, when a methane explosion at a nearby mine killed more than 100.

"The cause of the blast is being determined," the ministry said in a statement. A regional mining official said the explosion was caused by a concentration of methane gas inside the mine, where 252 people were working at the time.

Friday’s second accident took place at a mine in the neighboring Donetsk Region. The incident was caused when lifting equipment collapsed, killing seven people and injuring four others. The fate of four more miners remains unknown.

According to Ukraine’s Emergency Ministry, whose specialists are currently working at the site, 538 miners have left the tunnels using reserve portals.