Federal law enforcement is investigating a chilling threat to hit the Capitol building with a plane sent to New York air traffic controllers Monday, CBS reports. In an audio message, an unidentified voice says, “We are flying a plane into the Capitol on Wednesday. Soleimani will be avenged.” The threat arrived on the anniversary of the killing of top Iranian military official Qassem Soleimani by U.S. drone strike. Iranian leaders have vowed revenge in fiery rhetoric since the general’s death in January 2020. Federal law enforcement does not believe the threat is credible, but the Federal Aviation Administration has contacted authorities about investigating the breach of aviation radio frequencies, according to CBS. Congress is set to count and certify the results of the Electoral College’s vote Wednesday.