Washington In a step stemming from the FBI's terrorist attack probe, the U.S. government Sunday grounded crop-dusting planes across the country for the day.
It was the second time that agricultural pilots have been told not to fly since the Sept. 11 attacks.
Responding to questions about the latest grounding, the FBI said that it was one of the steps the bureau has taken out of "an abundance of caution" and "in reaction to every bit of information and threats received during the course of this investigation."
James Callan, executive director of the National Agricultural Aviation Association, said he got a call from a Federal Aviation Administration official about 8 o'clock Sunday morning.
"They said it was a national security issue," said Callan. "I made some calls and the indication was that there still is no specific threat, but the FBI apparently ordered this and they just want to make sure that everyone in the ag aviation industry is keeping their eyes and ears open."
FAA spokesman Scott Brenner said "the intelligence community came to us and encouraged us to shut down the crop dusters."
A notice on the crop dusters' Internet Web site stated, "Ag Aviators prohibited to fly on Sunday 23!"
Defense Secretary Donald Rumsfeld outlined the potential threat on CBC's "Face The Nation," saying that countries sponsoring terrorism have "very active chemical and biological warfare programs."
"We know that they are in close contact with terrorist networks around the world," he said.
Crop dusters also were grounded Sept. 16 and for the past week have been barred from flying over metropolitan areas, with some exceptions. The crop dusters were grounded along with all other civilian aircraft after the attacks, with flights resuming Sept. 14.
Callan said there are probably about 3,500 agricultural aviators and that this is a crucial time of the year for aerial spraying of crops.
As the FBI's probe continued, agents in a Dallas suburb arrested a Palestinian whose name turned up in the address book of a former personal secretary to suspected terrorist Osama bin Laden.
Ghassan Dahduli is appealing an immigration court deportation ruling for obtaining a work visa through fraud, FBI spokeswoman Lori Bailey said. Dahduli's name surfaced in records introduced at this year's trial of Wadih el Hage, who worked as personal secretary to bin Laden. El Hage and three other bin Laden associates were convicted of conspiring to murder Americans.