Israel carried out airstrikes on Gaza, killing one Palestinian and seriously wounding two, following two nights of rocket attacks that were the first since September, the health ministry said.
Dozens of pre-dawn strikes targeted bases of Gaza's Islamist rulers Hamas and allied militant groups, a Gaza security source said.
The Israeli army said the strikes targeted "a wide range of Hamas terror targets", including a naval base, a military compound and a weapons manufacturing plant.
The Hamas-run health ministry identified the person killed as Ahmed al-Shehri, 27.
It did not say whether he was affiliated with any armed group.
The sound of explosions was heard across the tiny but densely populated territory, AFP correspondents said.
After daybreak, curious onlookers gathered around a large crater scooped out of the sandy soil by the force of one of the blasts.
A Hamas source said it had fired at the Israeli aircraft carrying out the raids and the Israeli military confirmed fresh "incoming fire".
The strikes came after at least ten rockets were fired from Gaza at southern Israel late last night causing damage but no casualties.
The Israeli military said eight of the rockets were intercepted by air defences.
Air raid sirens sounded in Israeli communities near the border.
One family house was hit, without causing any casualties, the army said, posting a picture of the damage on Twitter.
It was the second consecutive evening that the army reported rocket fire from Gaza, shattering a calm that had lasted since 12 September.
In August, a spate of rocket attacks, retaliatory air strikes and clashes along the border had raised fears of an escalation as a general election approached in Israel.
Those polls, Israel's second general election this year, took place on 17 September, but have yet to yield a new government.
Sworn enemies Israel and Hamas have fought three wars in the Palestinian enclave since 2008.
Analysts say a fourth round remains likely.
There have been repeated bouts of violence between Hamas and Israel over the past year as the Islamists have sought to improve on the terms of a UN- and Egyptian-brokered truce first hammered out in November last year.
In return for Hamas silencing the rockets, Israel agreed a package of measures to ease the crippling blockade it has imposed on Gaza for more than a decade.
They included allowing in millions of dollars in aid from Hamas ally Qatar to pay for fuel for the territory's sole power station and cash for salaries and grants to tens of thousands of needy families.
The truce has also seen Israel expand the distance it allows Gaza fishermen out into the Mediterranean, although it reduces it or even cuts it to zero in response to violence from the enclave.
The concessions authorised by Prime Minister Benjamin Netanyahu have been criticised by his opponents, including by his challenger for the premiership, centrist former military chief Benny Gantz.
Mr Gantz called a renewal of the truce agreed by Mr Netanyahu in May "capitulation to blackmail".
The Palestinians have also pressed on with weekly demonstrations along the Gaza-Israel border first launched in March last year.
The protests have frequently drawn live fire from Israel forces stationed along the heavily fortified border fence.
More than 90 Palestinians were wounded in yesterday's demonstrations, the health ministry said.