“Stressors” caused by the ongoing novel coronavirus pandemic may trigger an increase in attacks on houses of worship once faith-based services resume, the U.S. Department of Homeland Security cautioned in a letter obtained by Politico this week.

The author of the letter, Brian Harrell, assistant director for infrastructure security at DHS, reportedly acknowledged that the department is not aware of any “imminent or credible threats.”

Nevertheless, U.S. officials have seen an increase in online hate speech “intended to encourage violence or use the ongoing situation as an excuse to spread hatred,” Harrell wrote.

“When you begin efforts to reconstitute services and welcome congregants back into your houses of worship, please also review your security plans and ensure procedures are in place to protect your facilities and visitors,” the DHS official suggested, warning that “stressors caused by the pandemic may contribute to an individual’s decision to commit an attack or influence their target of choice.”

DHS “provides resources that assist in securing physical and cyber infrastructure” for houses of worship, Harrell noted.

In January, Acting Homeland Security Secretary Chad Wolf reportedly directed the department to evaluate internal recommendations for thwarting attacks on faith-based communities and houses of worship in the wake of the mass stabbing at an upstate New York Hanukkah celebration last year.

ABC News reported on March 24 that DHS had disseminated a bulletin to law enforcement officials across the country, warning that violent extremists’ efforts to capitalize on the pandemic “will intensify in the coming months.”

On March 19, the FBI office in New York warned local police agencies that members of extremist groups were encouraging their followers to contract coronavirus and spread the disease to law enforcement officers and Jews, ABC News pointed out in a separate article.