ISRAEL’S latest strike on Lebanon crossed a “red line,” senior Hezbollah official Mahmoud Qamati said today, saying that the group’s leadership was considering whether to respond.

Israel struck Beirut for the first time since June on Sunday, killing Hezbollah’s chief of staff Haytham Tabtabai.

The attack on the city’s southern suburbs killed five people and wounded 25 others, Lebanon’s Health Ministry said.

“We will continue to act forcefully to prevent any threat to the residents of the north and the state of Israel,” Israeli Defence Minister Israel Katz said.

Israeli Prime Minister Benjamin Netanyahu accused Mr Tabtabai of leading Hezbollah’s efforts to rearm.

Israeli air strikes over southern Lebanon have intensified in recent weeks while Israel and the United States have pressured Lebanon to disarm Hezbollah.

The Lebanese government, which supports disarming Hezbollah, has denied Israeli claims that the group is rebuilding its military capabilities.

It also says its cash-strapped army, which has deployed to the south, needs more resources.

“Hezbollah’s leadership is studying the matter of response and will take the appropriate decision,” Mr Qamati said.

“The strike on the southern suburbs opens the door to an escalation of assaults all over Lebanon.”

Lebanon’s President Joseph Aoun condemned the strike and accused Israel of refusing to implement its end of the ceasefire agreement.

He called on the international community to “intervene with strength and seriousness to stop the attacks on Lebanon and its people.”

The strike hit the busy Haret Hreik neighbourhood without an Israeli evacuation warning.

“This is definitely a civilian area and void of any military presence,” Hezbollah parliamentarian Ali Ammar said.

Meanwhile, funerals were held in Gaza today for Palestinians killed in Israeli attacks despite a ceasefire being in place.

At least four people were killed in Gaza today, reports suggested.