Security officers were out in force at Los Angeles International Airport on Saturday, allegedly after officials found out ISIS called for attacks on uniformed personnel as part of a possible terror plot. The FBI is investigating and security is being increased at other airports in Southern California because of a 'known threat' to LAX from ISIS, according to a federal law enforcement official. The investigation and security increase started after intercepted communication and other intelligence information led officials to believe that a plot could be under way. Scroll down for video . Security is being increased at airports in Southern California because of a 'known threat' from ISIS at LAX . Officials found out earlier that ISIS called for attacks on uniformed personnel as part of a possible terror plot . The federal law enforcement official did not say whether this was a new threat. The Transportation Security Administration alerted local law enforcement agencies responsible for security at the other airports, although the possible threat was not necessarily related  to aviation, CNN reported. It added that some US cities had increased their security, but gave no further details. Officials are concerned about threats to uniformed personnel or locations that lone wolves may want to target, US officials told NBC News on Friday. Despite the new security increase, officials said the possible threat was not necessarily related to aviation . Los Angeles World Airports said: 'We are constantly adjusting our deployment strategies, and as a precaution, have increased the visibility of airport police.' LAWA is the airport oversight and operations department for the City of Los Angeles, according to the Orange County Register. A Department of Homeland Security spokesman would not comment on the specific intelligence. The spokesman did say: 'Over the last few months, we have made a number of security adjustments, including enhanced screening at select overseas airports and increasing random searches of passengers and carry-on luggage on flights inbound to the US, reflecting an evolving threat picture.' No one at the FBI was immediately available to comment. Homeland Security Secretary Jeh Johnson also declined to comment on the reported threat to LAX. No arrests have been made.
FBI investigating after intelligence information indicated possible terror plot . TSA involved although possible threat not necessarily related to aviation . No arrests have been made and it is unclear whether this is a new threat . In addition to Los Angles, some other US cities have increased security .