The military action came amid simmering tensions over President Trump’s Jerusalem declaration, injecting another layer of uncertainty in the area.
JERUSALEM — Israel said on Sunday it had destroyed a tunnel dug by Hamas from Gaza into Israeli territory, dealing a substantial blow to one of the main strategic assets in the Islamic militant group’s arsenal.
It was the second cross-border tunnel in six weeks that the Israeli military said it had detected and put out of use with new technologies, leading officials to predict the end of the cross-border threat from such tunnels.
“We have reached new technological capabilities in the struggle against terror tunnels,” Israel’s defense minister, Avigdor Lieberman, said in a statement.
Referring to Israeli border communities, he added, “I hope that in the coming months the tunnel threat to the residents of the ‘Gaza envelope’ will become a thing of the past.”
More immediately, the action against the tunnel injected another element of uncertainty into the simmering tensions over President Trump’s decision to recognize Jerusalem as the capital of Israel .
Clashes on Friday and Saturday between Palestinian protesters and Israeli forces in many parts of the West Bank and along the border with Gaza were not as huge as many had feared, and most had died down by Sunday.
The United States ambassador to the United Nations, Nikki Haley, noted the relatively low intensity of the backlash so far as she defended Mr. Trump’s declaration on Sunday.
“Everybody said the sky was going to fall,” she said in an interview with Jake Tapper on CNN. “The sky is still up there, it hasn’t fallen.”
Arguing that Mr. Trump’s decision could “move the ball forward” on the Israeli-Palestinian peace process, she said the administration “did not talk about boundaries or borders” of Israeli sovereignty within the contested city “for a reason. And that’s because whatever is East Jerusalem or any other part, that’s between the Palestinians and the Israelis. That’s not for the Americans to decide.”
There were some further disturbances, however.
The military wing of Hamas vowed to avenge the deaths of two militants killed by Israeli airstrikes, which were themselves a retaliation after a rocket was fired from Gaza into the Israeli border town of Sderot over the weekend. It smashed the window of an empty kindergarten.
“Our battle for Jerusalem continues hour by hour, over the ground and underground,” Hamas’s military wing said in a statement on Sunday.
In the Israeli-occupied West Bank, where the Western-backed Palestinian Authority exercises limited control, a Hamas leader joined his organization’s calls for a “Jerusalem intifada,” or uprising.
The mainstream Fatah party led by President Mahmoud Abbas of the Palestinian Authority also called for protests after Mr. Trump’s declaration and has disseminated some graphic images via social media to whip up emotions.
In Jerusalem, meanwhile, a Palestinian man in his 20s stabbed an Israeli security guard at the central bus station, severely wounding him, the police and medics said. The assailant was arrested at the scene.
A surge of Palestinian stabbings, shootings and car ramming attacks that began in October 2015 has claimed the lives of about 40 Israelis and others, including two American visitors. More than 250 Palestinians were killed during the same period, according to the Palestinian Ministry of Health, mostly while carrying out or trying to carry out attacks, by Israel’s count.
Most of the attacks on Israelis were carried out by so-called lone wolves, acting without the assistance of known Palestinian organizations and, in many cases, without any particular political affiliation. The violence had largely petered out over the past year.
Lt. Col. Jonathan Conricus, a spokesman for the Israeli military, said the tunnel destroyed on Sunday had been monitored by the Israelis for months. The decision to incapacitate it now, he said, despite the current tensions over Jerusalem, stemmed from what he called “the unknown part of the equation.”
“Those who are responsible for protecting Israeli civilians have to decide every day that goes by if it is worth waiting,” he said. The military, he added, “does not seek to escalate the situation.”
During the 2014 Gaza war, several Israeli soldiers were ambushed and killed by militants who emerged from underground tunnels. The Israeli authorities say the tunnels violate Israeli sovereignty and threaten civilians living in the border area.
The latest to be destroyed extended hundreds of yards into Israeli territory, according to the military, and ended in open farmland about a mile from the nearest Israeli village.
Israel has invested heavily in trying to thwart tunneling. It recently went public with its plans for a subterranean barrier, has been using virtual-reality systems to simulate fighting in tunnels and is training troops in mock-ups of mazelike underground networks.
Military and defense officials did not elaborate on the new tunnel detection and demolition system, but said it was a combined effort involving intelligence agencies, combat and engineering forces. Mr. Lieberman attributed the recent successes to the military, the Ministry of Defense and the defense industries.
The previous tunnel operation was in late October. The military identified what it said was a tunnel belonging to Islamic Jihad, which sometimes rivals Hamas, the dominant force in Gaza, but joins it in battle against Israel.
That time, Israel destroyed the tunnel by bombing it. Up to a dozen Islamic Jihad militants were killed in the tunnel’s collapse, as were two Hamas militants carrying out what the group called a rescue mission. It was the deadliest cross-border event since the 50 days of fighting in 2014.
This time, the Israeli military used a new, quiet and unspecified method of neutralizing a tunnel, and said it knew of no casualties.
