The IDF on Friday deployed Iron Dome batteries covering Ashdod and Netivot, following recent rocket attacks from Gaza.
The decision was made because of the risk that rogue organizations similar to supporters of the Islamic State, who appear to be interested in inflaming tensions, may continue to launch rockets.
Sirens sounded on Wednesday in Sdot Negev, Netivot, Bnei Shimon, and Ashkelon. Two rockets were found later, having exploded in open areas. The military struck three terror targets in the Gaza Strip in retaliation.
"The IDF views the incident gravely," said the military in a statement. "The Hamas terrorist organization is the address and the one on whom the responsibility falls."
Defense Minister Moshe Ya'alon echoed this message Thursday morning. "Even if last night's shooting at Israel was by errant global jihadist groups who wish to challenge Hamas by firing at us, we consider Hamas responsible for what happens in the Gaza Strip and we will not tolerate attempts to harm our citizens," he said.
A week earlier, a Grad rocket exploded in the Gan Yavne area. It was the first time since Operation Protective Edge that a mid-range Grad rocket was fired from Gaza.
A 15-year-old girl required medical treatment for anxiety.
The IAF attacked four targets in the southern Gaza Strip after that incident.
Security sources said they believe those behind the rocket launches are Salafists in Gaza who identify with the Islamic State organization and wish to take revenge on Hamas.