CNN reported over the weekend that the FBI has opened an investigation into a plot either directly from or inspired by ISIS that supposedly targets “parts of California.” The reporter doesn’t know whether this is a serious, acute threat or merely an aspirational plan, but the FBI is taking no chances:

The investigation originated from intercepted chatter and other intelligence information that led officials to believe a possible plot could be in the works, the officials said.

No arrests have been made. It’s not clear whether the threat is real or aspirational.

The exact nature of the threat couldn’t be learned. One official said it focused on parts of California where officials stepped up security, a U.S. official said.

The Transportation Security Administration alerted local law enforcement agencies that are responsible for external security around airports, but officials said the possible threat is not necessarily aviation-related.

If this seems vague, the steps it prompted appear a little more specific. DHS has beefed up its ESTA system for screening airline passengers, and security has been increased at federal facilities, CNN’s source at the agency told them. Their source didn’t give much hint as to what else might be happening.

Yesterday, the International Business Times reported that authorities had increased security at Los Angeles International Airport in response to a “known threat.” Authorities didn’t confirm or deny a connection to the FBI probe, but the timing looks coincidental otherwise:

Security has been tightened in Los Angeles and other locations of Southern California, including its airports after Intelligence reports hinted a fresh wave of ISIS- attacks, according to federal authorities. The FBI has taken up the investigation of the threat.

According to police, a known threat to Los Angeles International Airport has been confirmed, though it did not say it was a new one or something associated with Islamic State. Investigations started as soon as intercepted communication and intelligence information revealed a plot targeting parts of California, reported CNN. The Transportation Security Administration or TSA alerted local law enforcement agencies despite threat not being confined to aviation. There was no immediate comment from the FBI or Homeland Security Secretary Jeh Johnson.

Los Angeles is already using two-man police patrols as a precaution against lone wolf attacks. FBI Director Jim Comey has stated that investigations are on in all the 50 states to trace alleged ISIS sympathisers.  …

TSA was the first to come out with a classified warning that ISIS might be planning an attack on the U.S. soil. Driven by its imminence, TSA deployed its Visible Intermodal Prevention and Response teams or VIPR, at various locations. The teams are keeping surveillance at airports, train stations and other transportation hubs.

The nature of the threat prompting the response still remains murky. If it’s aspirational, then it has value in training for the real thing. If it’s more serious than just “aspirations,” the FBI and DHS have gotten a head start on it.