Israeli planes and helicopters have mounted at least seven missile attacks on Gaza, destroying what a military spokesman described as Palestinian munitions sites.
Witnesses and Hamas officials said four air strikes blew up two caravans near the town of Khan Younis. No casualties were reported.
Two children were wounded by flying debris after a fifth missile hit a cheese factory in Gaza City.
Helicopters struck twice in the central refugee camp of Nusseirat, destroying a metal foundry but no one was injured.
An Israeli military spokesman confirmed the attacks, saying they had targeted two weapons-manufacturing plants and two arms caches.
The air strikes were Israel's response to a Palestinian short-range rocket that was fired across the border into the Jewish state yesterday, the spokesman said.
The attack, which went unclaimed by any Palestinian faction, caused no damage.
Israel has said it will hold Hamas responsible for any attacks on its cities from Gaza.
