Israel is suspected of a major attack on Hezbollah in Lebanon on Sept 17, which involved exploding pagers that are said to have injured 2,750 people in the country.

According to The Wall Street Journal, the devices were part of a recent shipment to Lebanon and appear to have been rigged to detonate at the same time.

Here we explain why Israel is suspected of carrying out the attack, and the wider context of its conflict with Hezbollah.

Why is Israel at war with Hezbollah?

Hezbollah began firing rockets at Israel in response to the ground invasion of Gaza in October 2023.

Israel evacuated people living near the Lebanon-Israel border early on in the war, and has traded cross-border fire with Hezbollah ever since.

Tensions have recently spiralled due to the pager attacks and Israel’s killing of leading Hezbollah chiefs in an air strike on southern Beirut.

What is Hezbollah?

Hezbollah is a radical Shia Islamist paramilitary group based in Lebanon.

Backed by Iran, it is considered to be the most powerful and heavily-armed non-state actor in the world.

Its leader, Hassan Nasrallah, has claimed that the group could field more than 100,000 trained fighters, although independent observers believe that this is more likely to be 20,000 to 50,000.

Hezbollah is stronger than the cash-strapped Lebanese military, which has been reduced to selling tourist rides in its ageing fleet of 1960s helicopters. Lebanese soldiers also often take on second jobs to supplement their meagre $100 a month salary.

The terror group boasts a fearsome long-range armoury, which ranges from cheap ‘Katyusha’ rocket artillery to high-tech Fateh 110 precision-guided ballistic missiles.

Where did Hezbollah come from?

After Israel invaded Lebanon in 1982, forcing its long-term enemy the Palestine Liberation Organization to flee to Tunisia, it kept troops stationed in a southern buffer zone.

Disparate Islamist militias that continued to fight Israeli troops subsequently consolidated under an Iran-backed initiative that was to become Hezbollah.

The group pioneered modern terrorist tactics, such as suicide bombings and kidnappings, and fought against peacekeepers and international actors.

In 1983, it bombed the US embassy in Beirut, killing 63 people.

In 1985, it published a manifesto in which it pledged the destruction of Israel.

Hezbollah continued to fight against Israeli troops stationed in Lebanon until Israeli forces withdrew on May 25, 2000 – a day that is now a Lebanese public holiday.

Who was behind the pager attacks?

Israel has rejected claims that it was behind the clandestine operation to plant explosives in Hezbollah pagers and walkie-talkies, but experts believe that Mossad, Israel’s national intelligence agency, is responsible.

Israel is already strongly suspected of being behind the killing of Ismail Haniyeh, the Hamas political chief assassinated in Tehran shortly after meeting Iranian officials.

Israel generally has a policy of not commenting on attacks or assassinations carried out overseas, though its leaders do sometimes allude to them.

What happens next?

Israel could launch a full-scale invasion of Lebanon to remove Hezbollah from its strongholds in the south, the southern suburbs of Beirut and the northeastern Bekaa Valley.

It could also launch a limited invasion with the intent to create a buffer zone. Senior Israeli military figures have suggested occupying the area between the Lebanon-Israel border and the Litani River.

Tensions could also de-escalate. Although cross-border fighting between Hezbollah and Israel has been vicious, Hezbollah has yet to use its most devastating missiles, which suggests that Iran could be restraining the group.

What are the differences between Hezbollah and Hamas?

Hamas and Hezbollah are both Islamist groups committed to the destruction of Israel, but there are key differences and between them.

Hamas, a Palestinian organisation, is a Sunni offshoot of the Muslim Brotherhood. It has ruled the Gaza Strip since 2007 after it defeated rival group Fatah in an election and subsequent violent clashes.

Hezbollah is a Lebanese Shia group that was formed by Iran during the Lebanese Civil War to fight Israel. 

During the Syrian Civil War, Hezbollah supported the government of Bashar al-Assad while Hamas supported Sunni Islamist rebels.