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U.S. Secretary of Defense Leon Panetta is speaking out about the attempted attack on an Afghan base as his plane was about to land Wednesday, saying he doesn't believe he was the target.

"I have absolutely no reason to believe that this was directed at me," Panetta said in a news conference. "This is a war area and we're going to get these kind of incidents," AFP quoted him as saying.

Panetta was meeting with Afghan President Hamid Karzai Thursday.

In the strange incident, an Afghan man stole a truck, drove it toward the runway at Camp Bastion in Helmand as Panetta's plane was due to land, then crashed and exited the truck in flames.

A military source told Fox News the crash was an attempted attack, although it was unclear at the time who it was directed at. Fox News' source could not say whether the man knew Panetta was about to arrive.

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The Associated Press reported a senior U.S. official said they believe the attack was targeting a group of U.S. Marines assembled on the ramp, not the defense secretary. He said it would have been difficult to know which plane the defense secretary was aboard.

The attacker, who was identified as an Afghan interpreter, died Thursday from his injuries incurred in the crash, Newscore reported citing a U.S. military source.

The man was carrying gasoline and a lighter with him in the pickup truck, which he managed to steal from a British service member, sources told Fox News. The coalition service member was injured during the incident, possibly run over by the truck.

The attacker managed to drive the stolen vehicle over the very ramp where Panetta was set to arrive. The secretary was soon diverted to another ramp. After crashing the pickup truck into a ditch, the driver got out and had apparently lit himself on fire, according to this source.

Pentagon Spokesman George Little put out a statement earlier saying "no explosives were found."

Panetta was visiting Afghanistan to hold a series of meetings with troops and Afghan leaders in the wake of the killing of 16 Afghan civilians allegedly by a U.S. soldier.

"We will not allow individual incidents to undermine our resolve to that mission," he told Marines at Camp Leatherneck. "We will be tested, we will be challenged, we'll be challenged by our enemy, we'll be challenged by ourselves, we'll be challenged by the hell of war itself. But none of that, none of that, must ever deter us from the mission that we must achieve."

Panetta and other U.S. officials say the shooting spree should not derail the U.S. and NATO strategy of a gradual withdrawal of troops by the end of 2014. But it has further soured relations with war-weary Afghans, jeopardizing the U.S. strategy of working closely with Afghan forces on the transition.

Curiously, the more than 200 Marines who attended were told to take their weapons outside and leave them there before the speech.

"Something has come to light," Sgt. Maj. Brandon Hall told the troops. Asked about the order, Hall said all he knew was that "I was told to get the weapons out."

A U.S. defense official said the request was not a reaction to an immediate threat. The official said the decision was made out of respect for troops from other countries, such as the Afghans, who are never allowed to bring guns into an event. It was not a request from Panetta or his security team, the official said.

Fox News' Justin Fishel, Newscore and The Associated Press contributed to this report.