A law enforcement vehicle sits near the Congregation Beth Israel synagogue on Sunday, January 16, 2022, in Colleyville, Texas.
CNN  — 

Top officials with the Federal Bureau of Investigation and the Department of Homeland Security warned in a letter Monday that faith-based communities will likely remain targets for violence, urging state and local partners to evaluate their security postures for mass gathering events and at houses of worship.

“Faith based communities have and will likely continue to be targets of violence by both domestic violent extremists and those inspired by foreign terrorists,” said the letter from Paul Abbate, FBI deputy director, and John D. Cohen, the top intelligence official at DHS.

Online forums linked to domestic violent extremists have referenced Jewish targets tied to conspiracy theories about Covid-19, the outcome of the 2020 election and “even the Taliban takeover of Afghanistan and resettlement of Afghans to the United States,” according to the letter obtained by CNN.

The joint notice comes two days after the Colleyville, Texas, hostage standoff at Congregation Beth Israel, which the FBI is investigating as a terrorist incident.

The investigation into Saturday’s incident is still in its “initial phases,” the officials said, adding that “while this appears to be an isolated incident, and there are currently no additional specific and credible threats associated with it, we will continue to monitor all reporting to ensure this incident is not a catalyst for similar attacks.”

The officials pointed out that the US is in a period of “heightened threat,” which includes threats from domestic violent extremists and those inspired or motivated by foreign terrorists.

The threat is exacerbated by a divided society and the global pandemic, according to the letter, which says that in some cases, social stressors and other personal factors have mixed with ideological issues, resulting in violence.

“Foreign influence actors have also promoted narratives online intended to sow discord in the U.S. and foreign terrorist groups continue to encourage followers to conduct attacks and use social media to incite violence,” the letter notes.

On Sunday, Homeland Security Secretary Alejandro Mayorkas said DHS will work with Congress to increase funding so faith-based communities can upgrade their security and protect themselves against terrorism, hate crimes and targeted violence.

Congregation Beth Israel was a recipient of DHS grant funding as part of the Nonprofit Security Grant Program, according to Mayorkas.

Funding, which is administered through the Federal Emergency Management Agency, can be used in several ways, such as enhancing physical security, installing cameras, hiring security guards and cybersecurity upgrades. Other grant funding goes toward prevention and response programs to equip communities to identify when individuals are moving down the path to violence.

“This kind of threat did not begin when this attack started yesterday, and it will not end with the hostages free,” Mayorkas said during a media briefing.

He said the “harsh reality” is that there continues to be a “rise in the language of hate and its connectivity to violence.”

“We need to ensure that we not only protect our houses of worship and all places of assembly, but that we become aware of the signs that someone is going down a path toward violence,” Mayorkas told reporters.

CNN reported last week that a year after the attack on the US Capitol, homeland security and law enforcement officials nationwide were bracing for potential “unprecedented” levels of violence in the year ahead.

The country remains polarized, and many people are angry and frustrated about their individual selves or society’s conditions after two years of Covid-19 upheaval, turbulent economic conditions and government restrictions, sources and nongovernmental researchers told CNN.