Israel has launched a series of airstrikes in the Gaza Strip in retaliation for the deadly shooting of an Israeli civilian, killing at least two people, including a young girl, and wounding nine.
It was the heaviest flare-up of violence along the volatile border in months and threatened to destabilise a cease-fire between Israel and Gaza's Hamas rulers that largely has held for more than a year.
The Gaza Health Ministry said one airstrike killed a three-year-old girl and wounded three relatives, including two young siblings. He said a man was killed in an Israeli attack in northern Gaza. In all, nine people were wounded, one critically, he said.
Israel launched the airstrikes shortly after a Gaza sniper shot an Israeli civilian labourer as he worked on the border fence. The man was airlifted to a hospital, where he was pronounced dead.
The incident occurred as Israeli prime minister Benjamin Netanyahu was visiting the nearby town of Sderot, a frequent target of Palestinian attacks, to inaugurate a new rail line.
"This is a very severe incident and we will not let it go unanswered," Mr Netanyahu said. "Our policy until now has been to act beforehand and to respond in force, and this is how we will act regarding this incident as well."
Israel and Hamas are bitter enemies, but both sides largely have observed a ceasefire that ended eight days of heavy fighting in November 2012. The peace has been tested by periodic rocket and mortar attacks out of Gaza. Salafist extremists have been behind most of the violence, but Israel holds Hamas responsible for any attacks out of the territory.
Israel recently discovered a pair of smuggling tunnels leading from Gaza into Israel that it said were built by militant groups planning to stage attacks.