Palestinian terrorists in Gaza fired at least seven volleys of rocket fire into southern Israel on Monday afternoon and evening, undermining reports of a cease-fire.No injuries were reported from the rockets, but they prompted local officials to shut schools on Tuesday for the third day in a row.RELATED:Palestinian rocket fired from Gaza explodes near BeershebaIron Dome battery moved south after Gaza-rocket attacksClasses have been cancelled in Ashdod, Beersheba and Gan Yavne by municipalities and regional councils.The school closures were accompanied by reminders sent by authorities to residents on the need to remain in designated safe zones for a period of 10 minutes following the sounding of air-raid sirens.Drivers who find themselves on the road during a siren are instructed to pull over, exit their vehicles and head for a building or shelter.If none is in close proximity, motorists should lie on the ground and shield their heads with their hands.Meanwhile, Military Intelligence concluded that the video released by Islamic Jihad of a truck-mounted rocket launcher firing several projectiles successively was a forgery. The video had been released as part of a boast by the terror organization of improved rocket-firing capabilities. On Monday night, a Grad-type rocket fired at Beersheba was successfully intercepted by the Iron Dome anti-rocket shield, minutes after air-raid sirens rang out across the Negev city.Another rocket fell near Ashkelon, and three additional rockets landed in open territory around Sderot and the Sha’ar Hanegev Regional Council. Earlier, a rocket exploded south of Ashkelon, shattering a period of calm that had been in place since early Monday morning.No injuries or damages were reported in any of the attacks.Shortly after midnight on Monday, the Air Force struck a rocket-launching crew after it fired three rockets at the Eshkol Regional Council.“We identified an accurate strike,” an IDF spokesman told The Jerusalem Post.Defense Minister Ehud Barak said Monday the IDF does not pay attention to empty calls for cease-fires from various terrorist groups.In an interview on Monday with Army Radio, Barak said if they want a cease-fire, Islamic Jihad and Hamas will need to actually stop their attacks, he explained. He said Israel holds Hamas accountable for all rocket fire from Gaza. The defense minister said the IDF is not interested in returning to Gaza. It will, however, respond accordingly to attacks against Israel’s citizens.“There’s no foundation for charges that we are getting drawn [into the fighting] and not initiating. The people who call to us to attack forcefully in the strip will be the same people to criticize that we will get entangled there,” he said.Speaking at a B’nai B’rith event in Jerusalem on Monday night, US Ambassador to Israel Dan Shapiro strongly condemned the continued rocket barrage.“There is no excuse for attacking innocent civilians,” Shapiro said. “The US and Israel stand together in their fight against terror.”Tovah Lazaroff contributed to this report.