it is scam im working in tax collecting agency

Are u sure? He too confidently claims he is an IRS officer and when I asked, he also gave me a badge ID number... He says that he deals with criminal investigation branch of  IRS and his office is located at 1111 constitution Avenue.. When i tell him that I would go to local IRS .. He tells me that they would not know my case as it is a criminal case... Is this an IRS NUMBER ?

NO!!!!!!

So he said they wouldn't know your case? Thats a line of male cow bowel matter right there! All they have to do is pull you up on their computer! And like everyone has already said, the IRS does not call you, they send anything they have to do with you via snail mail. This is why he doesn't want you to go to the office personally, because they will tell you its a scam!

The IRS doesn't have any resources to shut down all those boiler room operations from overseas, or even the scammers here in the US.  And of course the caller sounds confident - he's a scammer and people fall for this scam all the time!

All you need to know is that the IRS does NOT call you out of the blue saying you owe taxes and you must pay them now or else you'll be arrested!  Doesn't work that way!  You're NOT going to be arrested if you owe taxes and haven't paid them.  Nor does the IRS call you and ask for payment at that moment, over the phone.

If you DO owe taxes, whether you just never paid them or made a mistake in your calculations, the IRS MAILS you a letter asking you to pay.  If by some chance, you didn't pay after receiving such notification, they would simply tack on late penalties and would take what you owe out of your next refund.  But please, don't take my word for it - go to http://www.irs.gov/uac/Contact-Your-Local-IRS-Office-1 and find the nearest office to call - they will confirm they don't call people like this.