robocall stating that there are criminal allegations against you. wants you to call back.
I got this call in quick succession to 253 336-5625 with a very similar message. likely they are linked.

Same call. Called back and got foreign accent person saying he was its and made no such call. Used my first name when all I shared was cell number. Said others have made similar call. Weird. I gave no info other than my cell they used and he had my first name and said nothing to worry about.

Same call and they left message about criminal allegations against me and I should call back.

I had a message about investigations.  I called the number just to see if I could tell where the call was coming from.  Heavy accented male answered the call and said he was with Robert Cooper's office with the IRS.  He used my name and I asked how he had my name when I didn't identify myself and I also questioned that this was a legitimate phone call.  He hung up on me.

I had a message about IRS criminal filing followed by another message from 360 450 0450 with almost the same message as if in tandem.  I have no plans to call back either.  My understanding is that the IRS only operates in writing.  I suspect this is a robocall to find operational phone numbers.