A3 World Briefing A10 NATION CHALLENGED A12-13 British Forces Hunt Qaeda and Taliban Fighters Hundreds of British troops, backed by artillery and American helicopters, have begun combat operations high in the mountains of eastern Afghanistan, British officials said.

NATION CHALLENGED 20-21 After Years of War, Afghans Return Home About 223,000 of the estimated 3.7 million Afghan refugees have returned home since a United Nations program to help them return began six weeks ago.

NATION CHALLENGED 18-19 U.S. Weighs Blueprint For Toppling Hussein The Bush Administration, developing a potential approach for toppling Saddam Hussein, is contemplating an air campaign and ground invasion of Iraq, with estimates of 70,000 to 250,000 troops needed.

NATION CHALLENGED 18-20 One American Killed In Attacks in Afghanistan Afghan and American forces attacked suspected Al Qaeda and Taliban fighters in eastern Afghanistan in some of the heaviest fighting of the war.

NATION CHALLENGED 26-29 U.S. Troops Lead Battle After Afghans Retreat American troops were unexpectedly forced into fierce fighting in Afghanistan last week after an allied Afghan general retreated under fire from foes who might have been tipped off about the attack, senior military officers said.

NATION CHALLENGED 12-14 Bin Laden May Be Alive, Officials on His Trail Say Fresh evidence suggests that Osama bin Laden survived bombing in Tora Bora and is probably hiding in mountains near Pakistan, officials said.

NATION CHALLENGED 14-17 Test of Guantánamo Conditions As More Prisoners Arrive Last week, 110 men were flown from Afghanistan to what is fast becoming a penal colony at Guantánamo Bay, with room being made for 1,900 more.

NATION CHALLENGED 14-16 Afghan Civilian Deaths Leave Families With Doubts Perhaps thousands of innocent Afghans have lost their lives during American attacks - including a raid last month under Pentagon investigation in which at least 21 suspected Taliban or Al Qaeda fighters died.

A NATION CHALLENGED Correction: December 10, 2001, Monday A picture caption on Wednesday about marines who flew helicopters in southern Afghanistan before heading north on a mission misidentified some of the craft shown.

NATION CHALLENGED 18-20 Broad Security Measures For American Weapons The Bush administration is taking wide measures to tighten scientific secrecy in hopes of keeping weapons of mass destruction out of unfriendly hands, including drafting a new information security policy, to be released in the next few weeks.