BEIRUT (Reuters) – Hizbollah vowed on Wednesday not to accept any “humiliating” conditions for a truce with Israel, as the Israeli killing of four U.N. observers piled pressure on an international conference in Rome to end the 15-day conflict. United Nations Secretary General Kofi Annan demanded an Israeli investigation into the “apparently deliberate targeting” of a U.N. post in southern Lebanon where an Israeli air strike killed the four U.N. military observers on Tuesday.

Israel agreed to Annan’s demand and Foreign Ministry spokesman Mark Regev said: “Israel sincerely regrets the tragic death of the U.N. personnel in south Lebanon.”

Full piece here.  This tragic circumstance, and an increasingly panicked humanitarian aid community, put increasing pressure on the U.S. to press Israel for a cease-fire.