The United States appears to be first in line to prosecute a man accused of plotting the Sept. 11 attacks, as Pakistani officials say they're willing to extradite a key al-Qaeda suspect to the U.S.

Officials confirmed on the weekend that Ramzi Binalshibh was arrested in Pakistan last Wednesday – on the first anniversary of the World Trade Center collapse.

Pakistani officials announced they had wrapped their investigation into Binalshibh's arrest Monday. The conclusion of the Pakistani investigation means he could be quickly transferred to the U.S.

Ramzi Binalshibh
Ramzi Binalshibh

FBI agents have taken charge of the man's interrogation in Karachi, Pakistani officials said. Another man suspected of being a high-level al-Qaeda member was also captured during the raid on the apartment building. He has not been identified.

Binalshibh, 30, is accused of helping mastermind the Sept. 11 attacks, and has appeared on Arabic TV in the past boasting about his role. The FBI believes he tried to become the 20th hijacker but was not able to get a visa to enter the United States.

Germany said Saturday that it wants Pakistan to extradite Binalshibh to Hamburg, where he is accused of being a member of an al-Qaeda cell. Authorities there have charged him with more than 3,000 counts of murder for allegedly planning the Sept. 11 attacks while on German soil.

Condoleezza Rice
Condoleezza Rice

But on Sunday, Germany's Interior Minister Otto Schily said that his government would wait its turn. "The terrible attacks of Sept. 11" took place in the United States, he said, so Washington has priority.

U.S. President George W. Bush's national security adviser said the White House is working closely with Pakistani authorities "to make certain that he gets to the right place" – the United States.

"We certainly want custody of him, and we certainly want to be able to find out what he knows," Condoleezza Rice said during an interview on Fox News Sunday.

"I think he's a pretty big fish. I mean, this is perhaps within the circle of those who were responsible for 9/11. And so, I think he is a pretty big catch," U.S. Secretary of State Colin Powell told CNN's Late Edition.

Others captured may be 'equally important'

Binalshibh was arrested after a four-hour gun battle in Karachi. Two other al-Qaeda suspects were killed, and seven police officers wounded.

Pakistan picked up at least nine other accused terrorists during a series of raids last week, and the men are now being interrogated. The White House may seek their extradition as well.

"The other people who were captured or killed here are perhaps equally important as to what happened with Binalshibh, but we will see who else was gotten in this raid," Rice said on ABC's This Week.

There are reports that authorities tracked down the al-Qaeda suspects after tracing a cellphone call.

The arrests have fuelled speculation that more Sept. 11 suspects may be hiding in Pakistan, including Osama bin Laden.

On the weekend, Bush said Binalshibh's capture proves that the U.S.-led campaign against terrorism is working. Arrests in New York state Friday night were also praised by the White House.

But Rice cautioned that the threat from al-Qaeda probably remains high. She said intelligence experts are not sure how decentralized the decision-making is within the terrorist network, and if sleeper agents abroad could be hatching their own schemes.

"It's not the organization that it once was, but we believe that the better part of valour is to continue to consider it a dangerous organization," Rice said.