The Israeli military has attacked several militant sites in Gaza in response to renewed border violence, with Hamas militants firing more than 30 missiles and mortars at Israel.
There were no reports of losses on either side, but the exchange threatened further attacks after weeks of tensions along the volatile border.
The military said its jets had attacked two Hamas tunnels and other military facilities, including those involved in the flood of fire kite and balloon attacks.
Even as the air raids were being carried out, the military said rockets were being fired at Israel. It was said six of them had been intercepted by the air defense system of the Iron Dome.
No injuries or damage were reported, but in the border communities the sirens waited much of the night.
In a relatively rare recording, Hamas said it fired the missiles to stop Israel from taking any further action.
Most of the recent Gaza rockets were fired by smaller factions. Hamas spokesman Fawzi Barhoum said it was an "immediate response" that should "convey the message".
Israel warned Hamas in recent weeks that although it has no interest in leading a conflict that has led to three wars in the past decade, the continued efforts of the Gaza militia to break the border and its campaign , would not tolerate ravaging Israeli border communities with arson attacks.
On Friday, thousands of Palestinians gathered near the Gaza border for their almost weekly protests. A 15-year-old Palestinian who tried to climb over the fence into Israel was shot dead. Later, the military said an Israeli officer had been moderately injured by a grenade thrown at him.
The Islamist militant group Hamas, which governs the Gaza Strip, has led border protests, some of which aim to draw attention to the Israeli-Egyptian blockade that was imposed after Hamas took control of Gaza in 2007.
The demonstrations were fueled by continued desperation from the blockade, which has led to a widespread economic emergency.
More than 130 mostly unarmed Palestinians have been killed by Israeli fire since the protests began on March 30.
Israel says it defends its sovereign frontier and accuses Hamas of using the protests as cover for attempts to break the border fence and attack civilians and soldiers.
In a statement, the military said Hamas' activities "violate Israeli sovereignty, endanger Israeli civilians and sabotage Israel's humanitarian efforts aimed at helping civilians in Gaza".