Since July 1, at least 48 coalition troops, including 24 Americans, have been killed in Afghanistan, according to iCasualties.org, an independent Web site that tracks military fatalities. There were 46 casualties in June and August 2008, which had been the deadliest months until Friday.

The spike in casualties comes amid one of the largest offensives since the war began in 2001. In recent weeks, 4,000 Marines have moved into Helmand, a Taliban stronghold, in an attempt to destabilize the insurgents' influence there.

With British support for the war in Afghanistan flagging and Prime Minister Gordon Browns government under fire following the deaths of 15 British soldiers in the past two weeks, the British press reported rising resentment over the heavy death toll in Afghanistan, where a surge in British casualties during an anti Taliban offensive this month raised the total number of British troops killed in Afghanistan to 184 — more even than in Iraq, where 179 British soldiers have died.