Bomb Explodes on Tel Aviv Bus on 8th Day of Current Conflict UPDATE: Israel and Hamas have agreed to a ceasefire. (AP Photo/Oded Balilty) A bomb exploded on a bus in downtown Tel Aviv on Wednesday, injuring at least 21 people, three of them seriously. The noon-time attack in the heart of the city came as Israel and Hamas had been trying to hammer out a cease-fire agreement to end this eight-day piece of a centuries-old conflict. (AP Photo/Oded Balilty) Lt. Col Avital Leibovich, the Israeli Defense Forces spokesperson to the international press, tweeted her suspicions: Don’t know who is behind Tel Aviv attack but in the early 2000s,50% of suicide bombers were #Hamas — Avital Leibovich (@AvitalLeibovich) November 21, 2012 The Izz ad-Din al-Qassam Brigades, the militant wing of Hamas, fired back at the IDF on Twitter, reiterating an earlier warning: We told you #IDF that our blessed hands will reach your leaders and soldiers wherever they are, “You opened the Gates of Hell on Yourselves” — Alqassam Brigades (@AlqassamBrigade) November 21, 2012 The last bus bomb attack in Tel Aviv happened in 2006. Follow Us Hamas spokesman Sami Abu Zuhri praised the bombing but did not claim responsibility. “Hamas blesses the attack in Tel Aviv and sees it as a natural response to the Israeli massacres…in Gaza,” he told Reuters. “Palestinian factions will resort to all means in order to protect our Palestinian civilians in the absence of a world effort to stop the Israeli aggression.” SEE ALSO: • Chilling Pics of Executed ‘Traitors’ Dragged Through Gaza • Smashing Heads: The Israel/Hamas Twitter War Gets Even Stranger • Peacemaker? Hillary Clinton in Middle East to Seek Truce So far, about 140 Palestinians have been killed in the week-old conflict, according to the Hamas health ministry, with more than 1,000 injured. Five Israelis have been killed, including the first military casualty on Tuesday. The Israeli military today said “800 rockets fired from Gaza hit Israel in the past week — 162 during the last day alone.” (AP Photo/Dan Balilty) The White House condemned the “outrageous” attack: “The United States condemns today’s terrorist attack on a bus in Tel Aviv. Our thoughts and prayers are with the families of those injured, and with the people of Israel. These attacks against innocent Israeli civilians are outrageous. The United States will stand with our Israeli allies, and provide whatever assistance is necessary to identify and bring to justice the perpetrators of this attack.” SEE ALSO: • Wolf Blitzer Runs For Cover as Sirens Go Off In Israel • Rupert Wants to Know Why ‘Jewish Owned Press’ Hates Jews Follow Us Slade Sohmer Slade Sohmer is editor-in-chief of HyperVocal and co-host of SiriusXM's daily "Politics Powered By Twitter" program. Tweet him at @SladeHV.