NEWS Los Angeles Airport Security Boosted Amid Possible ISIS Threat

Security is being stepped up in Los Angeles, its area airports and other parts of Southern California amid new ISIS-related threats calling for attacks on uniformed personnel, several U.S. officials told NBC News on Friday.

ISIS, which controls swathes of Syria and Iraq, has long called on its sympathizers to attack Western interests around the world.

Los Angeles had already started using two-man patrols as a precaution. Upgraded measures were extended to Los Angeles International Airport this week, officials said.

Investigators said there was no specific plot but concerns increased as a result of intelligence from overseas as well as ongoing monitoring of suspected radicals inside the United States. FBI Director Jim Comey has said investigations into suspected ISIS sympathizers are underway in all 50 states.

Fears revolve around threats to uniformed personnel or locations that lone actors may want to target, the sources said, speaking on a condition of anonymity.

A Department of Homeland Security spokesman would not comment on what specific intelligence has caused increased concerns along the West Coast. But, he added, officials had boosted security in recent months.

"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 U.S., reflecting an evolving threat picture," the spokesman said.

BY JONATHAN DIENST, ANDREW BLANKSTEIN AND RICHARD ESPOSITO