Just got the same call last night (at 5:50pm) - robot-sounding voice - saying that the IRS is suing me and that there is a "non-bailable arrest warrant" out for me. Did not bother to call back, because the IRS will not try to arrest you without visiting in-person first.
Total scam.
Another IRS Scam -Robotic voice left message saying " Hi this call is from internal revenue service. The reason we are trying to contact you is to inform you that there is a lawsuit filed against you by the internal revenue service and there is a nonbailable arrest warrant issued under your name, so before we move forward with a lawsuit and a legal allegation contact us as soon as possible on 206-201-2282 Thank you."