Palestinians in Gaza fired a rocket that exploded in an open field on the Israeli side of the border before dawn on Monday. No injuries or damages were reported.According to the IDF, no rocket sirens were sounded because the rocket was headed toward an open field.The IDF deployed Iron Dome anti-rocket batteries in the southern cities of Sderot and Netivot on Sunday, two days after a Gazan rocket fired by an ISIS-affiliated terror group slammed into Sderot, damaging a bus and a home. The air force's Active Defense Wing set up the two batteries days after it deployed an Iron Dome battery in Ashdod, which went into action on Friday night and fired an interceptor to destroy a Gazan rocket heading towards Ashkelon.The deployments reflect IDF preparations for potential additional attacks by the the Sheikh Omar Hadid Brigades, a Salafist organization affiliated with Islamic State, which said it was behind both rocket attacks on Friday.The Israel Air Force struck three terrorist targets in northern Gaza early on Saturday in retaliation, including a Hamas telecommunications site.The Omar Brigade is responsible for a growing number of rocket attacks from Gaza. It hopes to spark a new war between Hamas and Israel that will weaken Gaza's rulers and enable the Salafist group to fill the resulting power vacuum. Hamas arrested members of the group following past rocket attacks, and has stepped up attempts to enforce the August 2014 truce with Israel.Yaakov Lappin contributed to this report.