"The rescue workers who lost their lives last night attempting to reach miners in the Crandall Canyon mine are true heroes in every sense of the word. My thoughts and prayers are with their families and the families of the trapped miners whose fates are still unknown.
"In light of these tragic events, I will be joining with my colleagues on the Senate HELP committee to conduct a comprehensive investigation into the causes of this tragedy, the handling of the response, and the ways we can improve mine safety and rescue efforts across our nation."