DALLAS -- The FBI's chief spokesman during the Branch Davidian standoff near Waco, Tex., said there is evidence that David Koresh's top aide fatally shot the cult leader after apparently deciding the self-proclaimed messiah was a fraud.

FBI Agent Bob Ricks was quoted in the Dallas Morning News as having told a Tulsa civic group last month that Steve Schneider "probably realized he was dealing with a fraud."

Ricks reportedly said of the cult leader: "After he had caused so much harm and destruction, he probably now wanted to come out, and Mr. Schneider could not tolerate the situation."

Schneider shot Koresh and then killed himself, Ricks was quoted as saying. He could not be reached for comment.

As the FBI pumped tear gas into the compound "apparently many inside decided they wanted to come out. Over 20-some-odd people were shot that day," he was quoted as saying. "As a warning to others, they were shot and executed."

About 80 Branch Davidians died in the April 19 fire, which ended a 51-day standoff between cult members and federal agents.

Koresh's body was too badly burned to determine whether the single gunshot to his head was self-inflicted or a homicide, Tarrant County Medical Examiner Nizam Peerwani told the paper.

But Peerwani, who performed autopsies on the bodies recovered from the cult compound, said "it is possible" that the FBI's account of Koresh's death is correct. "The FBI has something we don't have: There were listening devices in there," Peerwani said.