CNN  — 

Federal and local law enforcement officials around the US are using an array of sophisticated tools and techniques as they continue to monitor for potential threats in the wake of Hamas’ attack on Israel, several law enforcement sources tell CNN.

FBI counterterrorism agents and analysts in bureau divisions continue to work “around the clock” to field tips from the public and monitor overseas online forums frequented by extremists, according to one federal law enforcement source who works national security cases.

Federal agents are also tasking human sources reporting on terrorism matters to help identify potential plots, another source said, and using informants to identify previously unknown email accounts, phone numbers and messaging apps used by known or suspected terrorists.

In a call with reporters on Saturday, FBI officials said the agency had seen an increase in reported threats against Jewish and Muslim Americans following the Hamas terrorist attack and were working to determine whether any were credible.

“We’ve been leveraging every tool at our disposal to protect the American people from extremist violence,” said one senior FBI official, including by “monitoring sensitive collection.”

Detection tools frequently used by FBI counterterrorism personnel include court-authorized monitoring under the Foreign Intelligence Surveillance Act, and so-called 702 collection authority for national security targets located overseas.

In a bulletin to private industry last week, the FBI and Department and Homeland Security said, “We do not currently have specific intelligence reflecting additional attack planning against the United States stemming from the Hamas attacks in Israel which began on October 7,” but warned the public to remain vigilant and report suspicious activity to law enforcement, noting, “In recent years, there have been several events and incidents in the United States that were purportedly motivated, at least in part, by the conflict between Israel and Hamas.”

Of particular concern to public safety personnel is the concept known as a “lone wolf” threat, one of the sources said Tuesday, a reference to an individual who may become radicalized to conduct violence but not part of a formal extremist group.

“A group of terrorists communicating with each other provides various avenues for possible exploitation using our surveillance capabilities,” the source said, but noted the more difficult task of detecting a lone individual who may not telegraph their attack plans to anyone.

While federal, state, and local authorities work behind the scenes to detect potential threats, police departments across the country continue to maintain visible enforcement postures in and around possible targets.

In Los Angeles, for example, the Los Angeles Police Department has adjusted patrol patterns to include frequent visibility around certain houses of worship and maintains continual outreach to the Jewish and Muslim communities, a law enforcement source told CNN Wednesday.

In addition to officers on the beat, LAPD’s Counter-Terrorism and Special Operations Bureau continues to monitor developments in the Middle East and the potential for events abroad to inspire violence at home, the source said.