FAA-aurora-1A fire at a Federal Aviation Administration outpost in Chicago that has grounded dozens of flights locally may in fact be arson, NBC News reported on Friday. Earlier, an NBC affiliate reported that the fire, which took place at a suburban Chicago FAA location, halted departing flights from O’Hare and Midway International airports. However, sources told NBC News that the fire may have been intentionally set. The incident comes amid heightening fears of terrorism and instability abroad. On Thursday, Iraq’s prime minister warned that elements associated with the terrorist group ISIS may be targeting subways in Chicago and New York.  According to NBC Chicago, local firefighters were called to the Chicago Terminal Radar Approach, with no reported casualties. O’Hare is the U.S.’s second-largest airport, carrying more than 15 million passengers yearly. 25 CNBC