WASHINGTON — The Department of Homeland Security issued an updated national terrorism bulletin Friday warning of continuing threats to the homeland from foreign and domestic terrorists, and from “individuals and groups engaged in grievance-based violence.”

The bulletin — the third of its kind issued by the Biden administration — warned of the influence of online forums and social media in the spread of “violent extremist narratives,” including those suggesting resistance to COVID-19 restrictions and that the 2020 election was marked by fraud. The bulletin also mentioned the risk of “targeted violence” around the 20th anniversary of the Sept. 11 attacks on New York and Washington and around religious holidays.

The publicly released bulletin followed DHS communications to state and local officials recently warning of potential violence that “may occur during August 2021” fueled by an “increasing but modest level of individuals calling for violence in response to the unsubstantiated claims of fraud related to the 2020 election fraud and the alleged ‘reinstatement’’’ of former president Donald Trump.

Growing threats reported by state and local election workers led the Justice Department this summer to announce formation of a task force that will work with federal prosecutors and the FBI to investigate threats of violence against election staff.

While previous DHS bulletins have focused on the threat from domestic extremists, the new alert emphasized the threat posed by online activity from foreign intelligence services and international terrorists as well as domestic actors.

It noted, for instance, that as the anniversary of the Sept. 11 attacks approaches, al-Qaida in the Arabian Peninsula recently released its first English-language copy of Inspire magazine in over four years, demonstrating that foreign terrorist organizations “continue efforts to inspire” people in the United States susceptible to violent extremist influences.

It said that U.S. adversaries - including the Russians, Chinese and Iranians — “have increased efforts to sow discord” by distributing “conspiracy theories concerning the origins of COVID-19 and effectiveness of vaccines; in some cases, amplifying calls for violence targeting persons of Asian descent.”

“It’s a message to the public that these online activities are dangerous, and they are fueling the current threat environment,” said a senior intelligence official familiar with the latest bulletin, who spoke on the condition of anonymity because of the matter’s sensitivity. It’s “a very strong statement” to the public about the danger presented by false narratives promoted online, the official said.

“We are saying very clearly that the spread of these conspiracy theories on COVID and on the election is fueling the current threat environment. And we are concerned that this activity will in fact inspire acts of violence,” the official said.

On social media, extremists have flooded platforms such as Telegram with messages promoting a gathering this week by Mike Lindell, the pillow entrepreneur, making the false case that the 2020 election was stolen by hackers who transferred Trump votes to Biden. The promotion of Lindell’s baseless claims by foreign actors was reported this week by the Coalition for a Safer Web, which monitors online threats.

The new DHS bulletin does not cite particular targets but says there are “continued, non-specific calls for violence on multiple online platforms associated with [domestic violent extremist] ideologies or conspiracy theories on perceived election fraud and alleged reinstatement, and responses to anticipated restrictions relating to the increasing COVID cases.”