IRS Scam. This is a known type of scam. They claim they are the IRS, that they are going to file a lawsuit against you or that you will be arrested very soon. The calls I have been getting are a robot telling you to call their number.
It is the old IRS scam call. This one originates from Montgomery Ala. I blocked the call and have received subsequent calls from Kentucky and Florida, same voice different cell phone numbers, 859-325-5602 and 786-314-7008. All are recorded on other websites as scamming numbers.