The 11 firefighters who were injured fighting a massive fire in downtown Los Angeles had an opportunity to thank the doctors and medical staff that helped save their lives.

A massive explosion involving a pressurized cylinder on a semitruck in the Los Angeles area on Thursday morning left nine firefighters injured, including two who were critically hurt, officials said.

A 45-year-old man has been critically injured in an explosion in Boyle Heights Thursday, according to the Los Angeles Fire Department.