WASHINGTON (CNN) -- The U.S. military's first and only study looking into ties between Saddam Hussein's Iraq and al Qaeda showed no connection between the two, according to a military report released by the Pentagon.

A U.S. soldier in front of a bus hit by a roadside bomb near Nasiriyah, southeast of Baghdad, Iraq, on Tuesday.

The report released by the Joint Forces Command five years after the U.S.-led invasion of Iraq said it found no "smoking gun" after reviewing about 600,000 Iraqi documents captured in the invasion and looking at interviews of key Iraqi leadership held by the United States, Pentagon officials said.

The assessment of the al Qaeda connection and the insistence that Hussein had weapons of mass destruction were two primary elements in the Bush administration's arguments in favor of going to war with Iraq.

The Pentagon's report also contradicts then-Secretary of Defense Donald Rumsfeld, who said in September 2002 that the CIA provided "bulletproof" evidence demonstrating "that there are, in fact, al Qaeda in Iraq."

Although other groups, like the September 11 commission, have concluded that there was no link between Hussein and al Qaeda, the Pentagon was able to analyze much more information.

The documents cited in the report do reveal that Hussein supported a number of terrorists and terrorist activities inside and outside Iraq.

"The Iraqi regime was involved in regional and international terrorist operations prior to Operation Iraqi Freedom. The predominant targets of Iraqi state terror operations were Iraqi citizens, both inside and outside of Iraq," according to the report. Read excerpts from report (pdf)

Most of the terrorism was aimed at keeping Hussein and his Baath party in power, according to Pentagon officials.

"State sponsorship of terrorism became such a routine tool of state power that Iraq developed elaborate bureaucratic processes to monitor progress and accountability in the recruiting, training and resourcing of terrorists," according to the report.

The report cited such examples as training for car bombs and suicide bombings in 1999 and 2000, both of which U.S. and Iraqi forces have struggled to contain since the rise of the insurgency in summer 2003. E-mail to a friend

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