OKLAHOMA CITY (AP) — Some worry the truth behind the Oklahoma City bombing will die on May 16 when Timothy McVeigh is executed.

A handful of survivors and even the bomber's former lawyer believe McVeigh hasn't been honest about who or how many people planned, financed and carried out the deadly blast.

"I don't know if the truth will ever come out," said Jane Graham, 61, who was injured in the April 19, 1995, bombing. "It's easy to put everything aside and blame one individual. I think everybody just wants to wipe it away."

Graham was buried under furniture in the Housing and Urban Development office on the ninth floor of the Alfred P. Murrah Federal Building.

Shortly before the explosion, Graham said she saw two mysterious men in the building. Her theory is that someone placed bombs inside the building and that the truck bomb was a decoy that killed only a few of the 168 victims.

McVeigh's former attorney, Stephen Jones, also believes there was a wider conspiracy.

"The bombing was the work of somewhere between six and eight people directly involved," Jones said. "He was a member of a terrorist group and terrorist groups protect their members."

Jones described his former client as clever, manipulative and cunning.

"Tim McVeigh is certainly capable of elaborate lies," he said.

Kathy Wilburn, whose two grandsons died in the Murrah building day-care center, thinks McVeigh deserves to die but doesn't want him executed.

"I believe with him goes the truth," she said.

Wilburn has spent the last six years doing research, including visiting terrorist-training compounds and white supremacist groups. She believes the bomb plot was concocted in Elohim City, a survivalist compound in eastern Oklahoma. She also thinks authorities may have had a warning before the 9:02 a.m. blast.

Wilburn's daughter, Edye Stowe, wants to know why no Alcohol, Tobacco and Firearms agents were killed and why most weren't in the building.

"Where the hell was the ATF?" Stowe said, still mourning her sons. "I want to know. All 15 or 17 of their employees survived, and they were on the ninth floor. Did they have a warning sign? Did they think it might be a bad day to go into the office?"

The FBI is confident all of those responsible for the bombing were arrested, Dallas-based special agent Lori Bailey said.

Terry Nichols was convicted on federal conspiracy and manslaughter charges and sentenced to life in prison. Michael Fortier is serving a 12-year federal sentence after pleading guilty to knowing of the bombing plan but not alerting authorities.

"There were literally over a billion records that were created because of our investigation," Bailey said. "As soon as a theory came out, we investigated it. We double-backed and triple-backed and interviewed and researched to see if there was any veracity to any of it."

McVeigh said in the book "American Terrorist," that Nichols helped mix the fertilizer bomb, but claims he alone carried out the bombing.

Other conspiracy theorists have launched Web sites, most claiming more than one bomb exploded and more than one man was responsible.

One conspiracy theory organization, The Oklahoma Bombing Investigation Committee, plans to release a report this month detailing its contentions.

Committee chairman Charles Key, a former state representative, says he doubts McVeigh will ever admit the bombing was the work of a wider conspiracy. But, he doesn't think McVeigh should be executed.

"Dead men don't talk," Key said.