By Rick Sallinger

DENVER (CBS4) – The man who headed the Colorado role in the FBI investigation of Najibullah Zazi says investigators originally feared Denver was to be the target of a 2009 Al Qaeda bomb plot. Jim Davis was special agent in charge of the Denver FBI office at the time.

Jim Davis (credit: CBS)

He says the FBI received a tip from a foreign intelligence agency of an email exchange between a Colorado man and an active Al Qaeda operations email address.

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The Pakistani ambassador to the U.S. was due to speak at “The Cell,” a counterterrorism education museum in Denver. Investigators were concerned that could be a target.

Najibullah Zazi (credit: CBS)

Davis, now a Chief Federal Officer for a rapid DNA test result company, says the information about a possible plot based in Colorado was unexpected.

“It’s not the sort of thing you would expect to happen in Denver, you think New York or (Washington) D.C.,” he said.

The longtime FBI agent calls the Najibuallah Zazi case, his best one.

Davis had been having a cookout with fellow agents when word came of a suspected al-Qaeda terrorist in their territory. Zazi then took off for New York City in a rental car from Colorado.

“Our concern was that he was trying to get away because something bad was going to happen here,” Davis said.

Zazi was followed by agents to New York City where the apartment where he staying was searched and his car was towed.

“It was illegally parked, but we caused it to be towed,” Davis told CBS4’s Rick Sallinger who covered the Zazi investigation at the time.

(credit: CBS)

After his computer with bomb making instructions was found, Zazi flew back to his Colorado and his apartment in Aurora. There he lied to CBS4 when asked about any connections to the terrorist group.

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“Bomb plot investigation? Of course not. I have nothing to do with Al Qaeda or any link with Al Qaeda,” he told reporter Raj Chohan.

With attention peaked, Zazi then voluntarily agreed to be questioned by the FBI.

“After he came and started to cooperate he gave us the exact details of what his plan was,” Davis said.

Najibullah Zazi (credit: CBS)

He says Zazi told them the plan was to use suicide bombers to attack the New York subway system.

“My impression of him was he was a pleasant young guy very courteous, respectful,” Davis said.

“But he wanted to kill Americans?” Sallinger asked.

Davis replied, “Absolutely.”

(credit: CBS)

The investigation revealed Zazi had purchased chemicals at a beauty supply store in the Denver area and even tested explosives.

“You and your agents saved a lot of lives,” Sallinger suggested. “Thank you for saying that. I think that’s true,” Davis said.

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Last week Zazi was sentenced in New York to 10 years in federal prison which is basically time served. The prosecutor and judge cited his “extraordinary cooperation” with federal authorities in providing information on several terrorism investigations. He could have received life behind bars.

Rick Sallinger