The Department of Homeland Security July 2 said it intended to keep the security advisory system at yellow, meaning an elevated risk of attack.
In the meantime, on-the-road truckers should maintain a watchful eye, said Todd Spencer, executive vice president of the Owner-Operator Independent Drivers Association.
"Truckers should be vigilant this weekend, especially when hauling fuel or chemicals or when refueling. They should look for equipment and people that seem out of place when they're around high-security areas," he said. "They also should take special care to make sure they are not being followed if they've got sensitive cargo. The main concern is that someone might place an explosive device on your truck or trailer. This has happened several times in other countries and could very well happen here."
In addition, Spencer said truckers hauling material that might be attractive to terrorists should always think about the nearest escape route should they get stuck in traffic.
As July 4th approaches, ongoing analysis of intelligence information and assessments show no specific, credible information identifying terrorist intentions to conduct attacks against National Independence Day celebrations or related venues, DHS said.
DHS added that although the recent publicized threat to the oil and gas sector cannot be corroborated, this sector continues to represent a high value target for the terrorists. Recent reports cited the possibility that Texas had been targeted for this kind of terrorist activity.
DHS said it would continue to coordinate with the intelligence community throughout the holiday period and provide immediate threat notification as warranted.
Meanwhile, DHS offered some tips for the holiday weekend:
Increasing the security of a particular type of target makes it more difficult for terrorists to strike successfully. Therefore, it is important for truckers on the road, business people, law-enforcement personnel and all other citizens to maintain awareness by looking for suspicious activity or "things out of place."
Maintain heightened status of security forces, maintain irregularly timed security sweeps and conduct identity checks.
Also, DHS is telling businesses that ID checks at security points should be considered in order to verify the valid business need for an approaching vehicle. So truckers should expect such checks.
DHS also warned that special vigilance should be maintained for multiple vehicles arriving outside the window of scheduled activities. The use of random or rolling patrol operations can be effective in signaling to terrorists that their chances of succeeding are minimal.
Finally, DHS encourages truckers and all others to report suspicious activities during all threat levels.
If there's trouble, federal agencies, private citizens and companies can call, (202) 323-3205, 1-888-585-9078 or local 9-1-1. Federal agencies, private citizens and companies may report incidents online athttp://www.nipc.gov/incident/cirr.htm.