Omer Barlev, a Labor Party legislator, said Mr. Abu al-Ata had been in the military’s sights for a long time, adding: “Why did Netanyahu change his position now?”
And the leader of the mainly Arab Joint List, Ayman Odeh, wrote on Twitter: “A cynical man who lost two consecutive elections will leave only scorched earth in a desperate attempt to remain in office.”
Tacitly acknowledging the need to address those allegations, Mr. Netanyahu appeared publicly alongside Israel’s military and internal-security chiefs. He said they had both recommended killing Mr. Abu al-Ata, and that his Cabinet had authorized it 10 days ago.
“We tried to prevent his activity in various ways, but without success,” said Lt. Gen. Aviv Kochavi, the army chief of staff, explaining his recommendation to attack Mr. Abu al-Ata.
In rare public remarks, the chief of the Israel Security Agency, Nadav Argaman, said Israel had been tracking Mr. Abu al-Ata’s movements for days as he moved from safe house to safe house. “He acted like a wanted man,” Mr. Argaman said.
With Mr. Gantz running out of time to form a government, meanwhile, the flare-up, and his support for the government’s actions, appeared to raise the likelihood of a unity government in which he would join forces with Mr. Netanyahu, perhaps even with Mr. Netanyahu remaining prime minister for a limited period. The two met later Tuesday for what a “security update.”
Avi Benayahu, a former army spokesman, wrote on Twitter that Tuesday’s fighting amounted to “concentrated baking powder for a national unity government.”
“Add in the early tip-off Gantz received about the action and the unreserved support for the operation from Blue and White leaders,” he added, “and you have a perfectly baked cake ready for eating.”
Isabel Kershner and David M. Halbfinger reported from Jerusalem, and Iyad Abuheweila from Gaza City. Ibrahim El-Mughraby contributed reporting from Gaza City.