WASHINGTON, Aug 1: Top US military leaders faced tough questioning on Wednesday before a congressional committee about why their campaign in Afghanistan has failed to track down Osama bin Laden and his cohorts.

“For me, Operation Enduring Freedom has become Operation Enduring Frustration,” Senator Max Cleland said.

The Democrat from Georgia referred to the ghost that continues to haunt US foreign and military policy to explain his worry: “One of the things I learned in Vietnam was, if the terrorist doesn’t lose, he wins, which is why I’m so committed, personally, to making sure that his end is in sight.”

Defence Secretary Donald Rumsfeld, who appeared before the Senate armed forces committee with Gen Tommy Franks, commander of US forces in the region, retorted, “That is exactly what we’re doing, and we’re doing it all across the globe, and people are getting arrested every day. Arms caches are being discovered every day. People are being interrogated. People are being detained.”

“You can be frustrated if you want,” Rumsfeld added. “I’m not. We have a serious effort going on.”

Although, he added, Al Qaeda’s abilities to function, recruit and train fighters had been impeded, he acknowledged that those advances did not eliminate the possibility of another strike on the United States.

Rumsfeld also made it clear several times during the hearing that he did not know where Osama bin Laden was.

“We do not know if he’s dead or alive,” the secretary said. “We do know that he is having a great deal of difficulty functioning. He may be dead. He may be seriously wounded. He may be in Afghanistan. He may be somewhere else. But wherever he is - if he is - you can be certain he is having one dickens of a time operating his apparatus.”

He said US intelligence and allies across the world were helping to locate Osama and added that if he were in western Pakistan, as is being alleged, he was confident the Pakistan government would go after him.

Testimony at the hearing also acknowledged the consequences of civilian casualties as a result of US military operations.

“Various polls and anecdotal evidence point to a resultant loss of Afghan public support for US military efforts in Afghanistan, and an accompanying loss of confidence in the government of President (Hamid) Karzai,” said Senator Carl Levin, who chaired the hearing.

Franks was asked about a July 1 US attack in which 54 civilians were killed when US planes bombed a wedding party. Franks said he and Rumsfeld had seen tapes from the flights and said “there was no question” that there was ground-to-air fire.

PROBE TEAM: A United Nations fact-finding team that accused US forces in Afghanistan of removing vital evidence from the scene of a fatal bombing raid was not qualified to make such an assessment, a UN spokesman said on Thursday.