Israel and Hamas agree to Gaza cease-fire While Israel and Palestinian factions trade fire, Secretary of State Hillary Clinton arrives in the region to broker a truce. Updated at 12:35 p.m. ET: Israel and Hamas have agreed to a cease-fire, the Egyptian foreign minister said Wednesday in a press conference, after eight days of fighting that have killed more than 140 Palestinians and five Israelis. The cease-fire is set to start at 9 p.m. Cairo time, Egyptian Foreign Minister Mohamed Kamel Amr announced alongside U.S. Secretary of State Hillary Clinton. "The United States welcomes the agreement today for the cease-fire in Gaza," Clinton said. Earlier, an explosion on a bus in Tel Aviv on Wednesday injured 19 people, three of them seriously, an official told NBC News. Tel Aviv police spokesman Micky Rosenfeld told the U.K.'s Sky News that the bus blast took place in the heart of the city and that the surrounding area had been cordoned off as police searched for suspects. "This was a terrorist attack," Ofir Gendelman, a spokesman for Israeli Prime Minister Benjamin Netanyahu, told Reuters. The White House condemned the attack as "outrageous." In a statement, it reaffirmed the United States' "unshakable commitment to Israel's security and our deep friendship and solidarity with the Israeli people." Shot dead, dragged through the streets: The fate of an alleged spy in Gaza Secretary of State Hillary Clinton arrived in Cairo on Wednesday, where she met Egyptian President Mohammed Morsi. Speaking earlier in Jerusalem, she assured Netanyahu of "rock-solid" U.S. support for Israel's security and spoke of seeking a "durable outcome" and of Egypt's "responsibility" for promoting peace. A bomb ripped through a bus in Tel Aviv on Wednesday, wounding at least 16 people. Hamas spokesman Sami Abu Zuhri praised the bombing, but stopped short of claiming 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. More photos: Explosion hits bus in Tel Aviv Sweet cakes were handed out in celebration in Gaza's main hospital, which has been inundated with wounded from the round-the-clock Israeli bombing and shelling, Reuters reported. Celebratory gunfire also rang out in Gaza City when local radio stations reported the news. Analysis: Why Hezbollah is sitting out the Gaza conflict 'We are very scared': Egyptians fear being mired in Gaza-Israel crisis 'Army must invade': In southern Israel, support grows for action in Gaza Americans caught in chaos of Gaza conflict Meanwhile, the head of Iran's powerful Revolutionary Guard has disclosed his country has given fighters in Gaza the ability to produce longer-range missiles on their own, without direct shipments. The comments, by Gen. Mohammad Ali Jafari, quoted by the semi-official ISNA news agency, offer some of the clearest insights on Iran's weapons support for Hamas. Previously, Iran denied it directly supplied Hamas with the Fajr-5 rockets being fired at Israel in recent days. NBC's Lawahez Jabari, Ian Johnston and Andy Eckardt, Reuters and The Associated Press contributed to this report.