Israel air strikes killed nine Palestinians in Gaza on Wednesday, medical officials said, raising the Palestinian death toll to 19 over a two-day escalation in violence since Israel launched strikes to kill an Islamic Jihad commander. Islamic Jihad confirmed that two of its militants were killed in separate strikes south of Gaza City during the morning. Medics later said another man was killed by an air strike while on a motorcycle. The bodies of six people killed in Gaza City were brought into Shifa hospital in taxis and ambulances early Wednesday, as relatives wept and screamed. Medics and witnesses said they were civilians who lived in densely populated neighborhoods.A father and his son were among the dead with another son badly wounded, said family members."They started this, we did not want war," said one grieving relative. The Israeli military said on Wednesday it had resumed attacking Islamic Jihad targets in the Gaza Strip. Air strikes took out at least three rocket launching crews, a military spokesman said.The worst fighting in months erupted on Tuesday after Israel killed Abu Al-Atta, a senior commander of the Iran-backed Islamic Jihad militant group, accusing him of masterminding and planning attacks against Israel.In response to the killing of Atta and his wife, Islamic Jihad fired about 200 rockets into Israel on Tuesday, resuming on Wednesday morning.Despite attempts by diplomats to restore calm, an Islamic Jihad official told Reuters that his group told mediators it intended to carry on its retaliatory attacks."Attempts to restore calm did not succeed, the Islamic Jihad see that it is time to respond to the assassination policy, which was revived by the Zionist enemy," the official said, asking not to be identified."The enemy will pay the price of its foolishness, and we are determined to confront this aggression with all our might."However, there was no sign that Hamas, the much larger Islamist group that controls Gaza, was inclined to be drawn into the fray. Hamas andIsrael have managed to defuse previous escalations and avoid a full-scale conflict for the past five years, after fighting three wars from 2008-2014.In Gaza, schools and most government offices remained closed for a second day, as were schools throughout much of southern Israel.Israel captured Gaza in a 1967 war and withdrew troops and settlements in 2005. The territory has been controlled since 2007 by Hamas after it ousted Fatah in a violent coup. Tovah Lazaroff contributed to this report.