(Bloomberg) -- Israel closed the Kerem Shalom humanitarian crossing into Gaza on Sunday after a rocket barrage was fired by Hamas from the southern Gaza city of Rafah, in an incident that could imperil delicate hostage and cease-fire negotiations. Most Read from BloombergFrance’s Macron Calls for Reset of Economic Ties With ChinaEverything Apple Plans to Show at May 7 ‘Let Loose’ iPad EventBerkshire Cash Hoard Scores Another Record as Earnings GainThe World’s Hunger for Salmon Is Linked to an Ec