TexasCHLforum.com

In short, put a sock in it Bloomberg -- this is a knowing and intentional fraud your "news organization" is running upon the public:

Bloomberg wrote:Boston bomber Tamerlan Tsarnaev’s name on a U.S. government travel-watch list should have kept him from boarding an airplane without some scrutiny, yet he could purchase semi-automatic handguns with none.

Local and federal law enforcement officials either don’t know or aren’t yet saying how Tsarnaev and his brother, accused of bombing the Boston Marathon, obtained the guns they later used to kill a university police officer and critically injure a mass-transit officer. They didn’t apply for Massachusetts gun permits, as required by state law.

The reason they're not saying how they got the guns is that there was no legal way for them to do so.

Here's the reality folks -- while it is legal for a resident of one state to cross a state line and buy a rifle in another, provided the laws of both states are complied with, it is not legal for a person to obtain a handgun in any state other than the one in which one resides.
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The reason the question hasn't been answered is that there was no lawful way for a person to sell or otherwise transfer to these people the handguns, as they required a license to acquire them in Massachusetts and it is flatly unlawful to transfer a handgun, whether by a dealer or private party, where the buyer and seller do not reside in the same state.

As such there was no lawful means by which anyone could have transferred the handguns to these two and there was also no lawful means by which they could have bought them, since they didn't have the required permits.