“Pakistani Taliban commander Baitullah Mehsud claimed responsibility for the attack on an immigration services center in Binghamton, N.Y., the Press Trust of India reported Saturday.
Mehsud said that a Pakistani and another man carried it out the attack, which left 14 people, including a man the police suspected of being the gunman, dead during a killing spree Friday.”
But the principal gunman was a 42 year old Vietnamese immigrant who had recently lost his job which is hardly the usual profile of an Islamist terrorist. (The news reports I've seen do not report the involvement of anyone else in the attack) The Pakistani Taliban has also been making boasts about their capability recently—talking about plans to attack the White House and such—and there must be a very significant chance that they are just opportunistically claiming responsibility.
In its report, the Press Trust of India stresses that the claim is seen by analysts as far-fetched. On the other hand, it does seem odd to make a claim that can be so easily disproved. But overall, I would suggest treating it with severe scepticism unless some more evidence emerges to support it.