Two Palestinian children, a brother and sister, were killed in Gaza on Saturday when shrapnel from an Israeli airstrike hit their home, medical officials said.
The strike was targeting four training camps for Hamas militants and came in response to the firing of four missiles from Gaza into open areas of southern Israel late Friday, according to a statement from the Israeli military.
Residents of Beit Lahiya, in the north of the Gaza Strip, said 10-year-old Yassin Abu Khoussa died when shrapnel hit his family home, situated near a militant training camp. His 6-year-old sister, Isra, was seriously wounded in the strike and later died at a hospital.
Their 13-year old brother was wounded but survived, according to Gaza's health ministry spokesman, Ashraf Qidra.
The house had already been partially destroyed during the most recent Israeli offensive in the Gaza Strip in 2014, but the family was still living there, local sources said.
The Israeli strikes hit five targets across the Gaza Strip, according to a statement from Hamas, the Islamist militant group that controls the Palestinian coastal enclave.
No organization has claimed responsibility for firing the four rockets into Israel, but Israel has said it holds Hamas responsible for any attacks launched from the Gaza Strip.
An Israeli military spokesman, Lt. Col. Peter Lerner, described the attacks as an effort to "threaten the security and safety of the people of southern Israel."
"The military will continue to act to protect those who threaten innocent lives and Israel's sovereignty," he said.
During the Gaza war of 2014, militants fired thousands of rockets and mortars into Israel, which responded heavily with airstrikes, naval strikes and later a ground invasion. In all, 1,200 Palestinians were killed, mostly civilians. Israel lost six civilians and 67 soldiers.
The war ended with a fragile cease-fire, and rocket fire tapered off.
The last missile attack from the Gaza Strip was in October 2015. In an ensuing airstrike by Israel, a 2-year-old girl and her pregnant mother were killed when their house collapsed.
FOR THE RECORD
March 14, 5:35 p.m.: An earlier version of this article said that four missiles fired from the Gaza Strip into Israel last week were the first such projectiles fired since October. The missiles were the first since October to prompt an Israeli response that led to Palestinian deaths.
A 5-year-old was killed in February when an unexploded shell thought to be a dud detonated, and several other Palestinians were shot dead during demonstrations near the border with Israel.
In contrast, violence has surged in the occupied West Bank and East Jerusalem, where nearly 200 Palestinians and 33 Israelis have been killed this year.
The next frontier in the conflict may not be the air but underground. The Israeli military has said Hamas militant fighters have been digging tunnels with the aim of reaching inside Israel to carry out more attacks. Israel is working on technology to detect and destroy such tunnels.