The explosion in Beirut came after Prime Minister Benjamin Netanyahu said that there would be a “severe” response for the Golan Heights attack, which hit a field where young people were playing soccer. Israel blamed Hezbollah, and the group denied responsibility for the assault, which landed in the Druse Arab village of Majdal Shams. Western officials had urged Israel to exercise restraint in its response.

In a statement, Israel’s military said its strike in Beirut on Tuesday had targeted a commander that officials believed was responsible for the rocket attack on Saturday.

Two Israeli security officials, speaking on the condition of anonymity to discuss sensitive details of the operation, said the target of the strike was Fuad Shukr, a senior Hezbollah official and close adviser to Hassan Nasrallah, the group’s secretary general. More than 90 minutes after the strike in Beirut, three Israeli officials said it was still not clear Mr. Shukr had survived.

At least one person was killed in the strike and another 35 people were wounded, said Lebanon’s health minister, Dr. Firass Abiad. All of the casualties were civilians, and at least three of those injured were in critical condition, Dr. Abiad said in a call with The New York Times.

Here’s what else to know:

• Hezbollah has been firing rockets and launching drones into Israel for months in solidarity with Hamas, leading to frequent Israeli military responses, and the cross-border volleys have forced tens of thousands of people from there homes. The hostilities have displaced about 60,000 Israelis and 100,000 Lebanese in the region.

• Both Israel and Hezbollah have for months argued that they are exercising restraint and that they do not seek a full-fledged war, preferring a diplomatic solution. Many Western nations, including United States, have repeatedly called again for the parties to avoid escalation. Hezbollah has said it will only stop its attacks if there is a cease-fire between Israel and Hamas in Gaza.

  “We do not believe that an all-out war is inevitable,” the White House press secretary, Karine Jean-Pierre, told reporters on Tuesday. “We believe that it can still be avoided.”

• Mr. Netanyahu visited the soccer field in Madjal Shams on Monday and said of the victims, “These children are our children, the children of all of us. Israel will not and cannot let this pass and carry on as usual. Our response is coming, and it will be severe.” Local residents heckled Mr. Netanyahu, telling him they had no security and chanting “Murderer! Murderer!” at him, videos posted on social media showed.

• Israeli analysts said Hezbollah was most likely aiming at a nearby army base on Mount Hermon and did not intentionally target the village. But the group’s use of inaccurate rockets in an area dotted with civilian communities could lead to the kind of unintended consequence that risk sparking an all-out war, they said.

• Since the strike on Majdal Shams on Saturday, there have been continued exchanges across the border, but they have seemed to fall within the bounds of the routine tit-for-tat of the past few months. On Tuesday, dozens of projectiles were fired from Lebanon toward northern Israel, killing one Israeli civilian in the border community of Kibbutz HaGoshrim, the Israeli military said. Hezbollah took responsibility for firing rockets and drones at Israel, including at a town near HaGoshrim. The Israeli military said it targeted the sources of fire on Israel.