This is the DEA scam. Special Agent Carl Thomas (fake) They advise agents are standing by with warrants for your arrest if you don't pay or transfer money to an account. They say you have bought drugs over the internet illegally and that's why there is a warrant for your arrest. It can go away if you pay them the money. If you ask to many questions the caller gets angry and starts yelling at you. He sounds like he is reading from a script.
I had a message on my voice mail from this guy today at 12:39 pm on 7/3/12 too. He said he was a DEA agent with a warrant to arrest me and search my property, but didn't say why. He spoke very slow and in a deep voice and said that I needed to contact him ASAP or I would be arrested within 24hrs. Instead of returning the call, I went directly to my computer and found the DEA's webpage and compared the contact numbers. Of course they did not match, but the call was from Washington, DC. I then performed a reverse phone look-up and saw that it was a cell phone number. Bizarre. Then I googled the number + Wash, DC+ DEA and found everyone's posts about this guy. Sounds like the same jerk. I will not return the call, even though it might be a fun thing to do by blasting him on the offensive since I have this knowledge beforehand. I'll call the DEA hotline and report it instead.