Work continues Thursday at the site of the World Trade Center towers after fires were extinguished on Wednesday.

SUMMARY:

More than three months after two hijacked planes slammed into the World Trade Center towers, firefighters Wednesday extinguished the fires in the rubble now known as Ground Zero.

Blimps and traffic helicopters are expected to be seen again in the skies above 30 metropolitan areas. The Federal Aviation Administration lifted restrictions implemented after September 11 that prohibited aircraft from flying over major cities if air traffic controllers could not monitor those crafts.

UPDATE:

Firefighters remain on the scene at the World Trade Center rubble in case clean-up crews uncover more hot spots, but fire officials report that fires no longer burn at that site. "We've stopped putting water on them and there is no smoking," said Chief Brian Dixon from the New York Fire Department.

Workers have removed more than 710,000 tons of debris and more than 135,000 tons of steel from the site.

After the terrorist attacks, the FAA restricted the use of private planes, news and traffic helicopters, banner towers, blimps and commercial sightseeing aircraft that fly according to visual flight rules. The agency banned those aircraft from flying near major cities, including Chicago, Los Angeles, San Francisco, Dallas, Miami and Atlanta.

The ban allowed planes to fly only according to instrument-rated rules, flights that could be tracked by air traffic controllers. Wednesday, the FAA lifted that ban. (Full story)

KEY QUESTIONS:

What effect will the delay in passing an economic stimulus bill have on the economy?

Should the federal government issue national security alerts in response to undisclosed, vague threats?

Are U.S. intelligence agencies better equipped to detect and prevent future homeland terrorist attacks?

What is the government doing to fortify homeland defense? Click here for more

What are tips to know in the wake of the attacks? Click here for more

WHO'S WHO:

George W. Bush: U.S. president Click here for more.

Laura Bush: First lady of the United States, she has become more visible since the terrorist attacks, making public appearances urging parents and teachers to help reassure children that everything is being done to try to keep them safe. Click here for more

Tom Ridge: Director of the U.S. Office of Homeland Security, a new Cabinet-level positionClick here for more

Richard Clarke: Head of efforts to safeguard information systems for the Office of Homeland Security Click here for more

Wayne Downing: Retired Army general tapped as deputy national security adviser Click here for more

Joe Allbaugh:The chief of the Federal Emergency Management Agency Click here for more

Dr. David Satcher: Surgeon General of the United States

Dr. Jeffrey P. Koplan: Director of the Centers for Disease Control and Prevention Click here for more

Rudy Giuliani: Mayor of New York Click here for more

Michael Bloomberg: Mayor-elect of New York

Anthony A. Williams: Mayor of Washington

Dr. Ivan Walks: Director of the Department of Health for the District of Columbia

Paul O'Neill: Treasury secretary

Norman Y. Mineta:Transportation secretary

Jane Garvey: FAA administrator

VICTIMS:

The latest figures provided by federal and local officials give the following numbers of people dead or missing from the September 11 attacks:

WORLD TRADE CENTER: According to New York City officials, the death toll is 2,992 -- 2,442 people missing and presumed dead, including the 157 on the two hijacked planes -- and 550 bodies have been identified. The toll has been steadily shrinking for a variety of reasons, including duplicate reports and confusion in the hours and days immediately following the attack.

PENTAGON: 64 dead on hijacked plane; another 125 missing and presumed dead

PENNSYLVANIA: 44 confirmed dead on hijacked plane

IMPACT:

The attacks of September 11 have sparked new debate about balancing the protection of U.S. citizens with the protection of the civil rights of those suspected of terrorism.

While the United States is proud of the freedoms and the legal rights guaranteed by the Constitution, authorities and many citizens have argued those people who seek to destroy America do not deserve such protections while they represent an ongoing threat to the country.

While those arguments continue, so do the threats against U.S. interests. Security remains high at airports, certain industries and many government facilities.