A three-year-old girl in the Gaza Strip has been accidentally killed by a rocket launched by militants toward Israel, a Palestinian medical official said.
Ashraf al-Kidra says the girl died when the rocket exploded in the northern Gaza Strip. Three other people were wounded.
He said it was not clear whether the rocket was misfired, or whether Israel's "Iron Dome" rocket defence system caused it to explode over Palestinian territory.
The Israeli military says militants fired a total of five rockets at Israel. It says two were shot down by the Iron Dome system, while one fell in an open area and two landed inside Gaza.
Israel responded with a series of airstrikes, saying it targeted five concealed rocket launchers, a weapons-manufacturing facility and a "terror activity" site.
Palestinian officials later said that three other people were wounded by the rocket fired at Israel, while another two were hurt by the Israeli airstrikes.
Israel military spokesman Lt Col Peter Lerner said Israel is "determined to act against those that strive to target Israel".
The area has seen an increase in violence over the past two weeks since three Israeli teenagers disappeared in the West Bank.
Israel has accused Hamas militants, who control Gaza, of being behind the apparent abduction. Hamas has praised the kidnapping, but said it does not know who carried it out.
Israel has been carrying out a broad ground operation in the West Bank, searching for the missing teenagers and arresting scores of Hamas operatives.
There have also been near-daily rocket attacks from Gaza, prompting Israeli airstrikes in retaliation.