Israeli air strikes on Hamas security targets in Gaza killed two Palestinians and wounded 30 people on Saturday, medical officials in the Islamist-ruled territory said, while heavier rocket fire by militants wounded an Israeli man.
The escalating violence undermined a shaky truce brokered by Egypt on Wednesday, which sought to calm the latest flare-up in fighting that began on Monday when an Israeli man and two gunmen were killed in a raid launched from Egypt's Sinai desert.
One of the victims was a Palestinian man killed in an Israeli air strike which targeted a motorcycle near a building in Gaza City, Hamas medical officials said. Ten other people were wounded in that attack.
In an earlier strike, a Palestinian militant from a pro-al Qaeda Salafist group was killed in northern Gaza, the officials said. Israel confirmed both strikes, but denied a report a six-year-old Palestinian boy had died in a separate air strike.
The Israeli strikes followed the fiercest rocket attacks on its territory in six days of fighting. Shrapnel from a rocket fired into the Israeli town of Sderot wounded an Israeli man in the neck just as he was trying to enter a concrete shelter.
After a relatively calm period, more than 150 rockets have been fired into Israel in the past week, the military said.
At least 15 rockets were fired at Israel on Saturday, nearly three times as many as the previous day, and at least six others were intercepted by the Israeli missile defence system, the military said.
Israel's military chiefs scheduled urgent consultations to weigh a "course of action", a military spokeswoman said. Israeli authorities also urged the roughly one million Israelis who live in the south to stay indoors or close to fortified shelters.
"Israel cannot be silent in the face of the recent days' events," Civil Defence Minister Matan Vilnai said in remarks released by his office.
"We regard Hamas as fully responsible for everything that is happening in the Gaza area. Israel is acting, and will continue to act, with a strong hand against those terrorists who want to escalate the situation in the area," Vilnai said.
Hamas Vows to 'Smash' Israel
Hamas's military wing, which had not claimed responsibility for any of the rocket fire in the past few days, said it was "ready to smash the Israeli arrogance in response to its aggression".
Hamas medical officials said a six-year-old Palestinian boy had been killed in an air strike and a that a baby had been hurt in a separate strike near the Egyptian border.
Israel denied involvement in hurting either of the children.
Lieutenant Colonel Avital Leibovich, an Israeli military spokeswoman, said on Twitter that the report of Israeli responsibility for the death of the six-year-old was the result of "false rumours" and that the boy had died due to an explosion of ordnance belonging to Palestinian militants.
Another Israeli military spokeswoman said she had no report of any air strikes in Rafah, where the baby was reported to have been hurt.
Israel confirmed its aircraft had struck three militant targets in Gaza in at least two predawn raids.
Nobody in Gaza claimed responsibility for firing rockets at Israel, but a security source said the missiles had been launched by members of the Salafi, two of whose militants were killed in Israeli raids on Friday.
Israel blamed the Salafis for Monday's cross-border raid from Egypt, after which Israel launched punitive air strikes on nearby Gaza, killing 11 Palestinians, many of them militants but also a 14-year-old boy.
Hamas militants had conditionally pledged to adhere to the truce brokered by Egypt if Israel also held fire. Israel never formally commented on the deal but its officials had pledged to respond to any rocket fire from Gaza.
Cairo has brokered such deals in the past and stepped in this time fearing the violence, which coincided with a keenly contested presidential race in Egypt, could spiral out of control.