A wave of deadly explosions of pagers and other electronic devices carried by militants in Lebanon has sharply heightened Pentagon concern about a potential ground war erupting in southern Lebanon between Israel and Hezbollah.

The Israeli military said it was striking Hezbollah targets in Lebanon on Thursday, shortly before the movement's leader was due to give a speech. It also said the military chief of staff had approved plans for Israel's north,

Hassan Nasrallah refused to say when or how Hezbollah would take revenge. As he spoke, Israeli fighter jets swooped low over Beirut.

Israel launched a series of strikes on Hezbollah targets Thursday as the war against the Lebanon-based group widened in the wake of two consecutive days of deadly explosions triggered in wireless devices.

The attack came as the militant group’s leader said two days of pager and walkie-talkie explosions amounted to a declaration of war.

The Israeli military launched a new wave of strikes against Hezbollah targets in Lebanon on Thursday, after two days of device explosions that left the Middle East fearing all-out war.

Israel Defense Forces on Thursday said it carried out airstrikes on Hezbollah sites in Lebanon, just days after a deadly wave of explosions around Beirut.

Israel bombed southern Lebanon on Thursday and said it had thwarted an Iranian-led assassination plot after explosions in booby-trapped radios and pagers in the past two days caused bloody havoc in the ranks of its arch-foe Hezbollah.

Lebanon is reeling after facing deadly back-to-back attacks targeting Hezbollah members – with pagers simultaneously exploding across the country on Tuesday, then walkie-talkies detonating in a similar fashion on Wednesday.