Eleven people, including children, were killed in a rocket attack on a football ground in the Israeli-occupied Golan Heights on Saturday, the Israeli military has said.
The Israeli military said the rocket was fired by Lebanese group Hezbollah and hit a football pitch in the village of Majdal Shams. Hezbollah have denied any involvement in the attack.
A further 20 people were wounded by the rocket, according to the Israeli military.
The attack is likely to draw a fierce response from Israel, which has exchanged intermittent fire across the Lebanese border with Hezbollah since the October 7 attack on Israel last year.
Israeli Prime Minister Benjamin Netanyahu was returning home as quickly as possible from the United States, his office said.
Mr Netanyahu warned that Hezbollah "will pay a heavy price for this attack, one that it has not paid so far", his office said.
A witness told Reuters: "It landed in the soccer pitch, all of them are children... many bodies and remains are in field we don't know who they are."
The IDF’s chief spokesman Rear Adm. Daniel Hagari said all 11 people killed were aged 10 to 20.
Foreign Minister Israel Katz said the country was approaching an all-out war against Hezbollah and Lebanon following the attack.
He told Axios: “The Hezbollah attack today crossed all red lines, and the response will be accordingly. We are approaching the moment of an all-out war against Hezbollah and Lebanon.”
Hezbollah spokesman Mohamad Afif denied “any relation to the Majdal Shams incident", adding: “All accusations [of the group’s involvement] are false.”
The White House called the attack “horrific”, adding: “Our support for Israel's security is iron-clad and unwavering against all Iranian backed terrorist groups, including Lebanese Hezbollah.”
The strike followed earlier cross-border violence on Saturday, when Hezbollah said three of its fighters were killed, without specifying where.
Israel's military said its air force targeted a Hezbollah arms depot on the border village of Kfar Kila, adding that militants were inside at the time.
Since early October, Israeli airstrikes in Lebanon have killed more than 450 people, mostly Hezbollah members, but also around 90 civilians and non-combatants. On the Israeli side, 21 soldiers and 13 civilians had been killed before Saturday.
Earlier on Saturday, at least 30 people died after Israeli airstrikes hit a school being used by displaced people in central Gaza, according to the Hamas-run health ministry.
The victims had been sheltering at a girls’ school in Deir Al-Balah and were taken to Al Aqsa hospital for treatment following the strike on Saturday.
The Israel Defence Forces claimed the strike had targeted a Hamas command and control centre used to store weapons and plan attacks.
