File Photo: Members of the Islamic State militant group.
The US Federal Bureau of Investigation (FBI) is investigating a possible Islamic State-inspired terrorism plot in the United States, CNN reported on Saturday, quoting law enforcement officials.
CNN said the investigation started after intercepted communication and other intelligence information that led officials to believe that a plot could be under way.
The network quoted an official as saying the plot focused on parts of California and that officials there had stepped up security.
The Transportation Security Administration had also alerted local law enforcement agencies responsible for security around airports in the state although the possible threat was not necessarily related to aviation, CNN said.
It added that some US cities had increased their security, but gave no further details.
No one at the FBI was immediately available to comment.
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