They're saying it was two Russians now on WCVB. Not sure how credible that is yet. On the other hand, the mere existence of that information on Punditpress is a

They're saying it was two Russians now on WCVB. Not sure how credible that is yet. On the other hand, the mere existence of that information on Punditpress is a good reason to doubt its accuracy. Update: It's semi-official now (on WCVB): the two men were apparently from Chechnya.