Kabul, Afghanistan ? An intense manhunt ultimately will net the United States’ No. 1 enemy, Osama bin Laden, but there is no telling how long it might take, the chairman of the Joint Chiefs of Staff said Friday during a whistle-stop visit to Afghanistan.

Gen. Richard B. Myers denounced bin Laden’s latest taped message, saying its barbarity was a reminder that U.S. forces are involved in “a fight for freedom and civilization.”

Two and a half years after their al-Qaida group organized the deadliest terror attack in history, bin Laden and his deputy Ayman al-Zawahri are still at large and believed hiding in the craggy mountains between Pakistan and Afghanistan. A dragnet involving thousands of troops also has failed to track down Taliban leader Mullah Omar or renegade Afghan warlord Gulbuddin Hekmatyar.

The reward for information leading to bin Laden’s capture was recently raised to $50 million.

In all, some 109 U.S. soldiers have died — 39 of them in combat — during “Operation Enduring Freedom,” which began in late 2001 in Afghanistan.