Nation

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A relative and senior aide of radical Shiite cleric Muqtada al-Sadr was killed Friday in the holy city of Najaf. The assassination threatens to raise tensions amid a violent standoff between al-Sadr's Mahdi Army and the U.S.-backed Iraqi government.

Flight delays continued Thursday as American Airlines moved to cancel another 900 flights and expectations grew that cancellations are likely to spread to other U.S. carriers as regulators tighten their safety audits of airlines.