Israeli warplanes hit Gaza
In a new flareup a week ahead of a general election in the Jewish state, the Israeli Air Force carried out strikes on "Islamic Jihad terror sites," a military statement said, without elaborating.
Palestinian security sources said the Israeli aircraft repeatedly hit a base of the radical group in the north of the coastal strip.
There were no immediate reports of casualties.
In what an army spokeswoman said was a separate operation, a military aircraft fired at "Islamic Jihad terror operatives preparing to launch rockets," from the northern Gaza Strip.
"A hit was identified," a military statement said.
Islamic Jihad said it carried out Sunday's rocket fire in response to Israel's killing of one of its fighters earlier in the day.
"The Palestinian resistance targeted Sunday evening the city of Ashkelon and the Gaza envelope with a number of rockets, as a response to the crime of the Zionist enemy," it said in a statement.
The rockets set off warning sirens in the southern city of Ashkelon and several other locations, while around 10 were intercepted by the Jewish state's Iron Dome missile defence system, the Israeli army said.
Others crashed into open fields. There were no reports of serious injuries.
"Twenty launches were identified from the Gaza Strip toward Israeli territory," a military statement said.
There was no immediate comment from Hamas, which rules the Gaza Strip and has fought three wars with Israel since 2008 but has struck a series of unofficial truce agreements with the Jewish state in the past year.
On Sunday morning, Israel's army said it had "spotted two terrorists approaching the security fence in the southern Gaza Strip and placing an explosive device adjacent to it".
"The troops opened fire towards them. A hit was identified," it said.
Islamic Jihad identified the dead man as Mohammed al-Naem, 27, a member of its armed Al-Quds Brigade forces.
A video later emerged on social media showing a bulldozer approaching a body while a group of young, apparently unarmed men, were trying to retrieve it.
The sound of gunfire is heard and the men ultimately run away as the bulldozer scoops up the body.
A tank can be seen positioned nearby.
The Gaza health ministry said two civilians were wounded by Israeli gunfire at the scene.
Israel's hawkish Defence Minister Naftali Bennett has pursued a policy of retaining the bodies of militants from Gaza as bargaining chips to pressure Hamas, which has held the bodies of two Israeli soldiers since 2014.
Hamas is also believed to be detaining two Israeli citizens who entered Gaza separately and whose families say suffer from mental illness.
Israel has a general election on March 2, its third in less than a year after deadlocked polls in April and September 2019.
Embattled Prime Minister Benjamin Netanyahu, facing trial over a series of corruption allegations, is again neck and neck with centrist challenger Benny Gantz, a former military general.
Hamas and Israel last fought a full-scale war in 2014 but smaller flareups are relatively common.
In November, Islamic Jihad and Israel fought a three-day conflict that left 35 Palestinians dead and more than 100 wounded, according to official figures.
There were no Israeli fatalities.