Ever since the country was savagely attacked on Sept. 11, the FBI has relentlessly investigated flight schools, airports, universities, mosques, Middle Eastern charities and Muslim communities, looking for connections to al-Qaida or other jihadist groups.

The only stone, it seems, the bureau hasn't been willing to turn over is its own investigation into the Oklahoma City bombing. Presumably, that's because the 1995 terrorist attack was the exclusive work of homegrown extremists Timothy McVeigh and Terry Nichols. Or was it?

Even though McVeigh went to his death denying any larger plot, serious questions remain unanswered. Did John Doe No. 2 ever exist? If so, who is he? If not, why did a second suspect initially emerge? What material or witnesses did the bureau use to create its three sketches of this alleged co-conspirator?

And then there's that troublesome FBI-authorized all-points bulletin issued just minutes after the truck bomb exploded. The alert sent members of Oklahoma City law enforcement searching for two Middle Eastern-looking men seen speeding away from the blast area in a brown Chevy pickup with tinted windows and a bug shield. The APB was abruptly cancelled several hours later without explanation.

The evidence that the Oklahoma City bombing involved a larger conspiracy, one with Middle Eastern connections, is compelling. And the trail begins with that mysterious pickup.

The week after the bombing, Jayna Davis, a veteran Oklahoma City reporter at KFOR-TV, got a tip, which began her investigation of a local property management company. Dr. Samir Khalil owns Samara Properties, and several former employees told Davis they had seen a pickup, matching the APB's description, at the office.

Davis discovered that Khalil, a Palestinian expatriate, had pled guilty in 1991 to several counts of insurance fraud and served eight months in a federal prison. Khalil's court papers indicated that the FBI investigated him for alleged connections to the Palestine Liberation Organization. But Khalil vehemently denied any PLO links. And he's never responded to my calls for comment.

Former Samara employees also told Davis that six months before the bombing, Khalil hired a group of Iraqi refugees to do painting and construction work. This group had allegedly fled Iraq to escape Saddam Hussein's regime. But a Samara employee told Davis he saw them cheering the terror attack and vowing to die in Saddam's service.

Davis then used surveillance camera to take pictures of these Iraqis. Eventually, she focused on one man, Hussain Alhussaini (also known as Al-Hussaini Hussain), who seemed to match the last FBI profile sketch and description of John Doe No. 2.

Over the next several months, she interviewed witnesses who said they saw McVeigh in the company of a Middle Eastern-looking man in the days and hours before the bombing. Using KFOR's photo line-up, they identified that individual as Alhussaini.

Perhaps the most intriguing statements she collected came from a host of staff members at a motel near downtown Oklahoma City. They reported seeing McVeigh with a number of Middle Eastern men at the site in the months preceding the bombing. Using KFOR's photos, those men were identified as Samara employees. Alhussaini was included in that group.

The motel witnesses also said they saw several of the Iraqis moving large barrels around in the back of an old white truck. The barrels, they alleged, emanated a strong smell of diesel fuel, one of the key ingredients used in the Oklahoma City bomb.

Davis also discovered that the mysterious brown Chevy pickup was impounded by the FBI on April 27, 1995. The pickup had been abandoned in an apartment building lot. According to the police report, the truck had been stripped of its license plate, inspection tag and all its vehicle identification numbers. It also was spray-painted yellow, but the original color was listed as brown. One resident at the complex told the FBI the driver was "clean-shaven, with an olive complexion, dark, wavy hair and broad shoulders," in his late 20s or early 30s and of Middle Eastern descent.

Davis also used a hidden camera to interview Lana Padilla, Terry Nichols' ex-wife, about Nichols' repeated trips to the Philippines, a hotbed for terrorist activity. "Tim bought Terry the first ticket for the Philippines," Padilla said. That trip occurred in 1989. His last visit came in November 1994.

Ramzi Yousef, the Iraqi convicted for masterminding the 1993 World Trade Center bombing and a plot to blow up U.S. airliners, operated out of Mindanao and Manila in the Philippines. Yousef received funding from Osama bin Laden. According to a motion filed by the McVeigh defense team, an American fitting Nichols' description met with Yousef in the Philippines in 1992 or 1993.

Davis eventually aired a number of pieces, taking care to disguise the Iraqi's identity. However, Alhussaini voluntarily stepped forward on June 15, 1995, to publicly claim that KFOR and Davis had labeled him as John Doe No. 2.

Alhussaini told Channel 9 in Oklahoma City he was living in fear. He claimed to be working at one of Khalil's properties when the bombing occurred. And he produced a handwritten time sheet as proof. The former Iraqi soldier also denied knowing McVeigh, and demanded a public apology from KFOR.

KFOR and Davis stood by their reports and countered with witnesses who contradicted Alhussaini's assertions, including the time sheet, which was labeled a fabrication. Alhussaini responded by filing a state civil libel suit. However, he withdrew the suit the day before a judge was scheduled to rule on KFOR's motion for summary judgment.

Meanwhile, Alhussaini's suit froze KFOR's coverage of the story. And Davis eventually quit after The New York Times bought the station and the investigation was stopped. The former reporter, who had collected 22 signed affidavits from the witnesses she interviewed, was called to testify before a state grand jury that examined the bombing in 1997. With the witnesses' permission, she gave the grand jury the affidavits.

Alhussaini then refiled his libel suit in federal court. Once again attorneys for KFOR and Davis filed for a dismissal. On Nov. 17, 1999, U.S. District Judge Tim Leonard granted their motion. In his ruling, Leonard stated that all the facts in Davis' report were either true or statements of opinion, and did not libel the plaintiff. Alhussaini then appealed the ruling. A hearing was held on Sept. 10; a decision is pending.

Alhussaini moved from Oklahoma City and was reportedly living in the Boston area. His lawyer declined to give me a phone number for his client.

According to 1997 medical records produced during his federal suit, Alhussaini said he had worked for a while at Boston's Logan Airport (where two of the planes were hijacked on Sept. 11). Quoting from those records, Alhussaini first told his psychiatrist that he had quit his airport job because, "If anything happens there, I will be a suspect." However, he later told his doctor that he "wanted to look for another job because he feels unsafe in the environment he works in, the airport, given the recent events involving his being previously suspected of involvement in the Oklahoma bombing."

Alhussaini's specific job at the airport was never identified. I contacted the Massachusetts Port Authority, which oversees Logan, to obtain dates of employment. A spokesperson said the agency would not release any information.

During the course of her investigation, Davis made contact with Yossef Bodansky, executive director of the 13-year-old Congressional Task Force on Terrorism and Unconventional Warfare. Bodansky told Davis the task force had warned of an impending Islamic-sponsored terrorist attack in America's heartland back in 1995.

On Feb. 27, 1995, the task force had issued its first confidential warning to federal agencies that Islamic terrorists "may soon strike Washington D.C., specifically the Capitol and the White House." This confidential alert, which he said was quietly distributed to federal intelligence agencies and law enforcement, claimed the attacks were to begin after March 21, 1995.

"Striking inside the U.S. is presently a high priority for Iran," stated the warning. The alert also stated that upcoming terrorist strikes might be directed against "airports, airlines and telephone systems." In light of Sept. 11, it was a telling note.

On March 3, 1995, the task force issued an update. This "super-sensitive" alert stated there was a "greater likelihood the terrorists would strike at the heart of the U.S." Bodansky also told Davis that after the truck bombing, he reviewed intelligence data that confirmed, "Oklahoma City was on the list of potential targets."

Bodansky gave Davis copies of the task force's original alert and some of his confidential notes detailing the update and Oklahoma City's target status. His material notes an independent warning from Israeli intelligence a month before the bombing. The warning indicated a terrorist attack was impending and that "lilly whites" would be activated. Lilly whites, Bodansky writes, were people without any background or police records who would not be suspected members of a terrorist group.

Now President Bush has labeled Iran, Iraq and North Korea an "axis of evil." And hyperbole aside, details of Iran's alleged involvement in terrorism were included in last summer's U.S. Department of Justice indictment issued in connection with the Khobar Towers attack in Saudi Arabia. Moreover, Bodansky told me that Iran and Iraq agreed to cooperate in terrorist operations against the West.

Over the past seven months, I reviewed all of Davis' documents, including the material she got from Bodansky. I also conducted my own follow-up interviews and found no holes in her investigation. As for Davis, she's tried twice to give her material to the FBI.

According to her attorney Tim McCoy, Department of Justice attorneys prosecuting Nichols rejected Davis' documents in 1997 because they didn't want more material to turn over to the defense. McCoy testified to this at a recent hearing in Nichols' state murder case.

In 1999, former FBI agent Dan Vogel accepted the material, but he said that higher-ups later rejected it because the agency questioned Davis' ownership rights.

I called the bureau but it declined to explain this strange turn of events. Perhaps if Vogel had been allowed to testify at a recent hearing in Nichols' Oklahoma murder trial, details would have been forthcoming. But the Justice Department refused to let him take the stand.

Is this a case of FBI incompetence, political interference or the Justice Department's desire not to complicate a seemingly open-and-shut case against McVeigh and Nichols? I don't know.

I do know that too many questions remain unanswered. And I wonder: If the FBI had followed through on these leads, might agents have turned up links to sleeper cells or the network that planned the Sept. 11 massacre?

Editor's Note: Syndicated radio talk show host Glenn Beck has made available a thorough set of references for this subject on his website: http://www.glennbeck.com/okc/index.htm.