At least 20 rockets and mortars were fired from the Gaza Strip at communities in southern Israel.
One rocket is reported to have landed in a residential neighborhood in the Wednesday evening attack.
Most of the rockets were fired at Sderot and Netivot.
The Code Red siren was sounded in several southern Israeli communities. Residents have been instructed by the Israel Defense Forces to remain in bomb shelters.
A rocket fired from Gaza landed in southern Israel overnight on Tuesday.
On Tuesday, a retaliatory strike on a terror cell in Gaza, that had fired mortars at Israeli troops performing routine work in the border area, killed three members of the Islamic Jihad terror organization.