JERUSALEM- The Israeli air force has hit seven suspected militant sites in Gaza while the Palestinian militants sent a rocket into southern Israel in a flare-up along the Israel-Gaza border.

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Gaza health official Adham Abu Salmia says three Palestinians were wounded in the airstrikes. One reportedly was a dairy factory.

The military said on Tuesday the airstrikes targeted smuggling tunnels and a weapons-manufacturing facility. It says some of the tunnels were dug so militants could infiltrate Israel to carry out attacks.

The military also says the airstrikes were in retaliation for the firing of 13 rockets and mortars at Israel this week.

Israel Radio says the rocket fired by Gaza militants on Tuesday landed near a nursery school. No serious injuries were reported.