A back-up of climbers on Mount Everest is being blamed for four deaths. Clarissa Ward reports on new safety concerns about overcrowding in an area dubbed the "death zone" on...

A new medial study is raising questions about an over-the-counter supplement: calcium. Cardiologist Dr. Suzanne Steinbaum speaks to the "CBS This Morning" co-hosts about the apparent link between calcium supplements...

"CBS This Morning" takes a look at some of the day's headlines from around the globe.

Republican strategist Mike Murphy talks to Charlie Rose and Erica Hill about Mitt Romney's uptick in Florida in one recent poll.

President Obama has stepped up his attacks on his Republican challenger Mitt Romney, who has indicated that he won't take it lying down. CBS News political correspondent Jan Crawford reports.

The Navy is investigating a fire aboard one of its nuclear attack submarines, the USS Miami, while docked at the Portsmouth Naval Shipyard, in Kittery, Maine. WBZ's Bree Sison reports.

Fire breaks out on a nuclear submarine in a New England shipyard. Also, Mitt Romney fights back against attacks on his business record. All that, and all that matters, in...

Man makes statements to police implicating himself, police say nearly 33 years to the day since 6-year-old boy vanished

Reactor was off and was unaffected; Flames impacted torpedo room, but no weapons on board; Cause of blaze being probed

Mariela Castro tells Calif. academic conference that Cuban-Americans supporting economic, travel restrictions "have no scruples"