if you have time, call them up and waste their time. every person on the line uses up a channel for their calls, which i'm sure is being routed to some bumhick place in india. which will cost them a pretty penny in connection fees. i just wasted 5 mins of their time. when they ask for a phone number/address i give them the FBI headquarters information
Claimed to be IRS, and have issued a warrant for my arrest. These people have loads of numbers they use same group called from 703-972-8956, 361-209-8676 and about four others. As soon as I block them they use another number
This number showed up on my phone as a voicemail, it didn't even show up on my call list. Started listening and something about "this is a serious matter, blah blah blah", I didn't even listen to the whole message before I blocked it. Idiot scammers. Junk caller, junk call type. Just block them.