An Israeli air strike on Gaza City killed one person and wounded another on Tuesday, Gaza's Hamas-run health ministry said.
"A man in his 20s was martyred and another injured in an Israeli air strike... in Shati refugee camp in western Gaza City," health ministry spokesman Ashraf al-Qudra told AFP.
It was the first deadly Israeli air strike since an Egyptian-brokered truce went into force on November 21.
The military confirmed it had carried out a raid but gave no further details.
Witnesses said the man who was killed was a 23-year-old member of a Salafi Islamist group, Haitham al-Mishal.
Over the last two months, there has been an uptick in rocket fire on southern Israel after more than three months of complete quiet following a deadly confrontation in November which ended with the Egyptian-brokered truce deal.
The latest firing was on Monday when a mortar shell struck an open area in southern Israel, a day after an Israeli air strike on southern Gaza. Neither incident caused any injuries.
On Sunday morning, Prime Minister Benjamin Netanyahu warned that Israel would retaliate with great force against any rocket or missile fire on Israeli territory.
"I want to make it clear that we will respond in a very offensive way against any rockets or missiles. We will take all necessary measures to ensure the security of Israelis... on all fronts," his office quoted him as saying.
According to army statistics, since the start of this year, 16 Gaza rockets have struck Israel, most of them in March.
"Sixteen rockets landed in Israel since the beginning of 2013, 90 percent of them in March," a spokesman told AFP on Monday.
"This figure includes only rockets that landed in Israeli territory. A larger number of rockets were fired against Israel but missed their target," he said.