Israel Air Force jets bombed tunnels along the Philadelphi Corridor and other Hamas targets throughout the Gaza Strip on Tuesday, in response to the firing of a Grad-model Katyusha rocket into Ashkelon earlier in the day. It was the first rocket to strike the city since Operation Cast Lead ended on January 18. The rocket struck in a residential area near the city's sports stadium, damaging homes and vehicles and sending three people into shock. An air raid siren rang out across the city in the seconds before the attack, sending residents fleeing for their safe rooms and bomb shelters. After the rocket struck, the IDF warned residents of Gazan Rafah to leave their homes. The recorded messages, in Arabic, said that people who worked in the tunnels, lived near them or provided logistical assistance to terrorists should evacuate the area immediately, residents said. Around 6 p.m., IAF jets struck back, bombing five weapons smuggling tunnels as well as a Hamas outpost. "I was out jogging when the siren went off," said Gad Manor, manager of the Neveh Ilan community center, whose home was damaged by shrapnel. A lieutenant-colonel in the IDF and a former paratrooper, Manor said he had not felt the need to stop jogging when he heard the siren. "When I heard the explosion, I knew it was near my house. When I got home, I saw pieces of shrapnel that had flown through my son's window into his bedroom. Another piece of shrapnel came in through the kitchen window. My family was in the safe room," Manor recounted. "My neighbor's home was more seriously damaged," he said. "The operation [Cast Lead] didn't do the job. A professional army wasted its energies. So long as we don't bring down a hostile regime, we haven't accomplished a thing," Manor said. "The rockets came back faster than we thought." Aviel Mirlashweli, 16, also heard the explosion from his home, though he was further away from the impact zone. "I think [the IDF] made a huge mistake in leaving Gaza," he said. "We were inside, we should have finished them off." Shortly after the rocket attack, Ashkelon Mayor Benny Vaknin held a situation analysis meeting and consulted with military officials, before deciding not to send the city into emergency mode, and to keep the schools open. "We will not let terrorism dictate our lives," Vaknin said. "Studies will go on as normal, and all educational facilities will remain open for students." He also called on the government to immediately provide rocket-proof structural reinforcements on every school in the city, starting with the 10 schools and 22 kindergartens that have no protection whatsoever. Earlier, confusion reigned after a committee of parents released a statement calling on the public not to send children to school. "The committee should have taken part in the meeting with all of the professional sources before releasing its statement," Vaknin said. Later on Tuesday, Prime Minister Ehud Olmert, Foreign Minister Tzipi Livni and Defense Minister Ehud Barak convened a meeting to discuss Israel's responses. The decisions taken during the meeting were kept secret, but Mark Regev, a spokesman for Olmert, issued a warning to Hamas that it would face grave consequences if rocket fire continued. "Hamas is playing with fire, and they alone will be responsible for the destruction of the 'quiet,'" he said. "The whole international community will understand that if there's a new escalation, it will be the direct result of Hamas's extremist, irresponsible and nihilistic behavior." Security officials, meanwhile, said Hamas was directly responsible for the latest violation of the two-week-old cease-fire, and added that Israel would not return to the situation that existed before Operation Cast Lead. They noted that 19 rockets and 12 mortar shells had been fired at Israel since the conclusion of the offensive. In Cairo, a Hamas delegation began a last round of cease-fire talks with Egyptian officials led by intelligence chief Omar Suleiman. Hamas sources reported that a deal could be struck this week, but only if Israel agreed to open the border crossings. Israel has linked the full opening of the crossings to the release of kidnapped IDF tank gunner St.-Sgt. Gilad Schalit. "I advise Hamas not to play hardball with us," Barak said after Tuesday's rocket attack. "We will not allow the situation in the past to return, and the Grad that landed in Ashkelon will not go unanswered." Livni backed a swift and strong military response to all rocket attacks. "My opinion on this matter is clear: Every attack must be met with a response," Livni told Radio Jerusalem. Likud leader Binyamin Netanyahu visited Ashkelon after the Grad attack and promised that a government under his leadership would stop the rocket fire and overthrow Hamas. "Tzipi Livni and the leadership of Kadima scoffed at my predictions regarding rocket fire," Netanyahu said. "The policy of blindness followed in the past years has brought us to this situation. Residents can no longer count on miracles and Kadima policy." Jerusalem Post staff and AP contributed to this report.