Washington ? Despite a massive number of tips, rumors and other intelligence, the U.S. military has never had good enough information on Osama bin Laden’s whereabouts to mount a mission to go after him, Defense Secretary Donald H. Rumsfeld said Wednesday.

Some intelligence officials disagree, saying bin Laden probably was at his Tora Bora stronghold during December airstrikes but escaped because too few American troops were committed to the hunt.

“We have seen repeated speculation about his possible location,” Rumsfeld said. But the pieces of information “haven’t been actionable, they haven’t been provable, they haven’t resulted in our ability to track something down and actually do something about it.”

Senate Majority Leader Tom Daschle, D-S.D., said in a separate news conference that bin Laden and his top lieutenants must be hunted down.

“The bottom line is that we’ve got to find him,” Daschle said, adding that the al-Qaida operatives at large are “still capable of inflicting real harm” on the United States.

They were responding to a Washington Post report that the Bush administration believes the gravest error of the war was not sending more American troops into Tora Bora.

Rumsfeld said that at the time of the assault he didn’t and now doesn’t have sufficient evidence that bin Laden was there “or that he left Tora Bora at the time, or even where he is today.”

Rumsfeld defended Gen. Tommy Franks’ running of the war, in which local Afghan fighters have been used as the largest portion of ground forces with U.S. air support and advice from special forces.

“What has taken place has been, under Gen. Franks, a very successful effort in Afghanistan,” Rumsfeld said.

U.S. intelligence officials said Wednesday that bin Laden probably was at Tora Bora in late November, left in early December after bombing began and escaped south toward the Afghanistan-Pakistan border.

Officials, speaking on condition of anonymity, cited two pieces of evidence: interviews with prisoners captured in the Tora Bora region and a radio transmission intercepted in early December that U.S. personnel identified as from bin Laden. Officials said other evidence exists but declined to go into detail.

But the intelligence assessment is by no means certain. Prisoners’ stories haven’t always added up, and the radio transmission could have been relayed from elsewhere as a trick.

To act, the military would have needed to know bin Laden would be at a certain place, at a certain time. The interrogations weren’t done until after Tora Bora was attacked, defense officials noted.

When the war started, bin Laden was believed to be in the Jalalabad area, moving between the city and a farming compound where his family lived, according to local officials. He is thought to have moved frequently in a large convoy, before heading south toward Tora Bora. He may have been wounded during the attacks there, although officials have no direct evidence of it.

A U.S. official said bin Laden is thought to still be in Afghanistan, but may have crossed over the border into Pakistan.

He may have also left his large entourage behind, opting to travel with a small group of followers to avoid U.S. detection. An unpublicized videotape, found in February by Afghan allies, shows bin Laden camping with only a few other people, according to published reports.

Another tape, broadcast Monday on Arab TV station Al-Jazeera, showed him kneeling beside a top deputy who proclaimed the terror attacks a “great victory.” It was unclear how long ago the tape was made and officials suspected it wasn’t in the last few months.

But it served as a fresh reminder that the administration doesn’t know where bin Laden is.

“I’m not ashamed to say we don’t know,” Rumsfeld told reporters Wednesday. “We don’t know.”