The Department of Homeland Security reissued a bulletin on Wednesday summarizing the terrorism threat to the U.S. homeland.
The National Terrorism Advisory System bulletin is an update released regularly since 2015 that describes "current developments or general trends regarding threats of terrorism," according to DHS.
"Terrorist groups continue to inspire, enable, and direct their followers to spread chaos using homemade weapons and by striking soft targets and crowded places," DHS said in a statement. "They also remain focused on conducting more sophisticated attacks using conventional weapons as well as new technologies and tactics. DHS is committed to staying a step ahead of our enemies, and an informed and vigilant public remains one of the Department’s greatest assets in protecting the homeland."
In the updated bulletin, which will be active until Sept. 14, 2018, the DHS warns terrorists' tactics have continued to evolve and now include the use of commonly found weapons for small-scale attacks, including straight-edged blades or knives, vehicle ramming, small arms, poisons, and homemade explosives. The bulletin also warns experienced foreign fighters could attempt travel to the United States from abroad in order to carry out an attack.
We continue to face one of the most challenging threat environments since 9/11, as foreign terrorist organizations exploit the Internet to inspire, enable, or direct individuals already here in the homeland to commit terrorist acts. Homegrown terror suspects increasingly rely on technology, such as end-to-end encrypted social media applications, to avoid detection.
Terrorist groups are urging recruits to adopt easy-to-use tools to target public places and events. Specific attack tactics have included the use of vehicle ramming, small arms, straight-edged blades or knives, homemade explosives, and poisons or toxins.
Some terrorist groups overseas are using battlefield experiences to pursue new technologies and tactics, such as unmanned aerial systems and chemical agents that could be used outside the conflict zones. Additionally, terrorists continue to target commercial aviation and air cargo, including with concealed explosives.
Violent extremist media encourages individuals worldwide to launch attacks using all means possible. Continued U.S. and partner successes in disrupting and defeating terrorists on the battlefield may encourage homegrown terrorists to carry out acts of violence in the homeland instead of attempting to travel overseas to fight or in retaliation for apparent losses.
Additionally, foreign terrorist fighters who have acquired training and battle-tested terrorism experience may flee from terrorist-controlled territories with a desire to conduct attacks elsewhere, including the United States.
The department notes that in an effort to combat the evolving threat and protect the American public, it is working with other agencies, especially the FBI.
"DHS remains committed to preventing violence and threats meant to intimidate or coerce specific populations on the basis of their religion, ethnicity or identity," the bulletin reads.
DHS calls on people to be prepared, stay informed, and report suspicious activity or information about a threat so that officials may investigate and prevent any potential attacks.