San Francisco joins lawsuit over halt in counterterrorism funding

San Francisco has joined a multi-city lawsuit against the U.S. Department of Homeland Security, or DHS, over its decision to halt a key counterterrorism grant program that supports detection and prevention of radiological and nuclear threats.

City Attorney David Chiu said in a statement that San Francisco is backing the legal challenge, originally filed by the city of Chicago. It claims that DHS unlawfully froze funding from the Securing the Cities program. 

The program was created under a 2018 law signed by President Donald Trump during his first term. It was designed to help urban areas develop the capability to detect and respond to nuclear and radiological threats. The grant provides more than a million dollars annually to the San Francisco Bay Area for terrorism prevention efforts.

Local officials say the freeze threatens public safety, especially with major global events like Super Bowl LX and FIFA World Cup 2026 approaching. 

The DHS did not immediately give a statement about the amended lawsuit.