Bush attends the ceremony where new U.S. Department of Homeland Security Secretary Michael Chertoff was sworn-in to office in Washington.(Reuters)

BEIJING, Mar. 4 -- US President George W. Bush says the United States has been in constant pursuit of Al-Qaeda leader Osama bin Laden and his associate Abu Mussab al-Zarqawi, head of the Iraqi branch of the group.

    Speaking at the swearing-in ceremony of Homeland Security Secretary Michael Chertoff, Bush said bin Laden's message is a telling reminder that Al-Qaeda still hopes to attack Americans on their own soil.

    He added that stopping them is the greatest challenge of the day. And American people will do everything in their power to meet that challenge.

    Speaking later at CIA headquarters, Bush confidently predicted that bin Laden's capture was all but certain.

    Bush said it's only a matter of time before he is brought to justice.

    On Monday, a US counterterrorism official said bin Laden suggested that Zarqawi may be involved in attacks inside the United States.

    (Source: CRIENGLISH.com)