By Joe Grossman

WASHINGTON, Sept. 26, (UPI) - - Up to 20 people arrested by federal authorities in connection with the terrorist attacks of September 11 allegedly obtained or attempted to get state licences to transport hazardous materials. Authorities are concerned that such materials, such as gasoline or other volatile or poisonous substances could be used in a terrorist attack. Attorney General John Ashcroft told the Senate Judiciary Committee on Tuesday that the FBI has advised all law enforcement agencies to remain alert for such an attack.

A Federal Bureau of Investigation spokesperson told United Press International that, "The FBI continues to investigate the up to 20 individuals who allegedly acquired or attempted to acquire hazardous material transportation licenses. The FBI and the department of transportation have asked the trucking industry to watch for suspicious activity involving hazardous chemicals and other dangerous substances."

The people who allegedly applied for the hazardous material licences may have links to the 19 men who hijacked the four airliners used in the attacks on September 11. On Tuesday, Attorney General John Ashcroft told the Senate Judiciary Committee that, "Today I can report to you that our investigation has uncovered several individuals, including individuals who may have links to the hijackers, who fraudulently have obtained, or attempted to obtain, hazardous material transportation licenses."

Ashcroft said that the FBI has advised all law enforcement agencies to remain alert for such an attack.

Susan Dryden, a spokeswoman for the U.S. Department of Justice, told UPI that there was no more than a suspicion at this point that those arrested have links to the terrorists who perpetrated the September 11 attacks. Dryden would not comment on how it was discovered that some persons suspected of having connections to the terrorists had applied for hazardous material licences. "That's all part of the investigation. . . .All of this information is still under investigation," she said. " Dryden said. Dryden would not say where the 20 suspects were being detained.

Although standards for the transportation of hazardous materials are set by the Federal Motor Carrier Safety Administration of the U.S. Transportation Department, licensing and testing is done at the state level and requirements vary from state to state.

A spokesperson for the California Department of Motor Vehicles said that in order to obtain a license to transport hazardous materials a person would need to first obtain a commercial driver license and pass a written test in the English language. Proof of legal residence in the United States would need to be demonstrated as well as having a social security number and being certified as medical fit.

A report by the Health and Human Services Agency for Toxic Substances and Disease Registry notes that it would be routine for terrorists "to use chemicals commonly found in communities in industrialized nations to create improvised explosives, incendiaries, and chemical agents. Common chemicals may be used because standard military chemical agents may be difficult or dangerous to manufacture, access, or disperse."

The report, "Industrial chemicals and terrorism: Human health threat analysis, mitigation and prevention," states that although the chemical agents that terrorist procure and develop might be less toxic than military supplies that they have tremendous impacts. According to the ATSDR report, 93 percent of domestic terrorism incidents involved an explosive or incendiary device.

A person driving a tanker tuck full of hazardous materials would have many options for terrorist actions.

Some of the substances that could be used in a terrorist attack involving hazardous materials are eye, skin and respiratory irritants, such as acids, ammonia, acrylates, aldehydes, and isocyanates; choking agents such as chlorine, hydrogen sulfide, and phosgene; flammable chemical industry gases such as acetone; aromatic hydrocarbons that could be used as water supply contaminants such as benzene; oxidizers for improvised explosives such as oxygen and peroxides.

Other possibilities are compressed hydrocarbon fuel gases that could be used as incendiaries or simple asphyxiants, such as liquified natural gas, propane, and isobutane; liquid hydrocarbon fuels that could be used as incendiaries or water supply contaminants, such as gasoline and, jet fuel; industrial compounds that could be used as blister agents such as dimethyl sulfate; and organophosphate pesticides that could be used as low-grade nerve agents.

(Reported by Joe Grossman in Santa Cruz, Calif.)