Defense Minister Amir Peretz ordered the IDF on Sunday morning to carry out an investigation into the previous night's targeted killing of Muhammad Dadouh - considered Islamic Jihad's most senior military commander in the Gaza Strip - in which Hanan Aman, 25, her five-year-old son and the child's grandmother were also killed and five other bystanders wounded, including Aman's three-year-old daughter. Although Peretz expressed regret for the death of innocent civilians, he said he would continue to authorize strikes targeting terror leaders in Gaza responsible for missile attacks, "in particular those behind the recent Grad-type launchings," a military official said. The army said that in addition to several other attacks against Israeli targets, Dadouh was personally involved in the firing of a Grad-type Katyusha rocket that fell near a Netiv Ha'asara farm last Tuesday, killing 30 chickens. That attack was the third time Gaza terrorists fired a Katyusha. Security officials estimated that terrorists have between 10 and 20 of the Russian-made rockets, supplied by Iran and smuggled into Gaza via Sinai. On Tuesday, the army played down the most recent attack, saying it was not an escalation in the conflict. However, security officials admitted the longer range of the rockets (up to 20 kilometers) and larger warhead capacity constitute a greater strategic threat than Kassam rockets. Islamic Jihad vowed to take revenge for Dadouh's killing. Dozens of gunmen gathered at the hospital and fired in the air, while other people cried. "Today we have lost another hero, but, God willing, the Israeli government will drink the same bitter drink that Dadouh's family and our people have been swallowing for a long time," said Abu Ahmed, the spokesman for Islamic Jihad's military wing. "The blood and the flesh of our leader today is the fuel for the resistance vehicle. There will be no limitations and no borders for our coming reprisal. All possible means of resistance will be used," he said. Dadouh was the third member of his family to be killed in a targeted killing. His brother was killed two months ago when a booby-trapped car blew up in Gaza.