IDF aircraft struck at least four targets in the Gaza Strip on Friday, a day after a rocket fired from the Palestinian enclave killed a Thai worker in Israel, Hamas security officials and witnesses said.
The Palestinians reported that two people were lightly injured in the strikes, whose targets included a smuggling tunnel along the border with Egypt, two open areas in Khan Younis and a metal foundry near Gaza City.
The IDF had no immediate comment.
Vice Prime Minister Silvan Shalom had said Israel would offer a strong response to what was the first deadly rocket fire from Hamas-ruled Gaza at Israel in more than a year.
Israel also sent a letter of complaint to United Nations Secretary General Ban Ki-moon, who is due to visit Israel at the weekend, and to the UN Security Council.
A previously unknown group, Ansar al-Sunna, believed to share the hardline ideology of al-Qaeda, claimed responsibility for the rocket fire at Israel, as well as the al-Aqsa Martrys Brigades, a wing of the Fatah movement.
Earlier, Deputy Defense Minister Matan Vilnai said that Israel holds Hamas accountable for attacks originating in the Gaza Strip regardless of the group that commits them.
"Israel is not interested in a military confrontation, but will not allow attacks on its citizens. Hamas must prevent any and all attacks on Israel to avoid a deterioration of the situation," he said.
Hanan Greenberg contributed to the story