"However, militants in the Al Aqsa Martyrs' Brigades, a violent group with ties to Palestinian leader Mahmoud Abbas' Fatah (news - web sites) movement, said the Lebanese guerrilla group Hezbollah was involved in the attack."
That's BS. They would have you believe that guerillas infiltrated across the Lebanon-Israeli border and made their way down to Tel Aviv undetected? Or that they made some kind of amphibious landing? Don't think so.
Most likely, this originated in the West Bank and they came across someplace where the fence is not yet finished. If I had to guess, I'd say some faction of Al-Aqsa (most likely Arafat cronies who got purged) are behind this. The objective is to provoke an Israeli counterstrike and discredit the Palestinian leaders who kicked them out of power.
Could be a "show of force" prior to the terrs' "meeting" or to disgrace Abbas before he goes to the EU - both in a few days time.
http://www.haaretzdaily.com/hasen/spages/545022.html
I'm watching what I believe is a live feed via BBC. The reporter in Tel Aviv is saying authorities are almost certain it was the work of a suicide bomber. And, the BBC anchor is saying that Reuters is saying the Islamic Jihad is claiming responsibility.