An American contractor working with the U.S. Army warned at least four years ago about a large cache of potentially explosive chemicals that was stored in Beirut’s port in unsafe conditions, according to a United States diplomatic cable. The presen...

An American contractor spotted and reported the potential danger at least four years ago, but U.S. officials denied they were aware of the findings until last week, after the blast. An American contractor working with the U.S. Army warned at least f...