A top United Nations official on Friday urged all countries with influence over Israel and Lebanese militant group Hezbollah "to leverage it now" to avoid an escalation of Middle East violence that she warned could dwarf the devastation seen so far.

UN political affairs chief Rosemary DiCarlo briefed the Security Council after attacks in which Hezbollah's pagers and walkie-talkies exploded, killing 37 people and wounding thousands. The attacks were believed to have been carried out by Israel, which has neither confirmed or denied its involvement.

"We risk seeing a conflagration that could dwarf even the devastation and suffering witnessed so far," DiCarlo told the 15-member council. "I also strongly urge member states with influence over the parties to leverage it now."

For nearly a year Israel and Palestinian militants Hamas have been at war in the besieged Gaza Strip. During that time Hezbollah has also been rocketing Israel in sympathy with the Palestinians and tens of thousands of people have been evacuated from homes on both sides of the Israel-Lebanon border.

Lebanon's Foreign Minister Abdallah Bou Habib accused Israel of carrying out the attacks and told the council: "No one in this world is safe any more." He showed the council a large picture of a bloody hand with missing fingers.

"We came to the council to protect our common humanity and to ask you to condemn the terrorist Israeli attacks clearly and unequivocally, to hold Israel accountable for planning and implementing these attacks and for violating the sovereignty of Lebanon and its territorial integrity," he said.

Israel killed a top Hezbollah commander and other senior figures in the Lebanese movement in an airstrike on Beirut on Friday, vowing to press a new military campaign until it secures the area around the Lebanese border.

Israel's UN Ambassador Danny Danon told the Security Council that Israel does not seek a wider conflict, but that it will not allow Hezbollah to continue its provocations. He accused Hezbollah of violating international law.

UN human rights chief Volker Turk said it was "difficult to conceive" how the attacks on Hezbollah's communications devices this week conformed with international humanitarian law. He called for an independent, thorough and transparent investigation and for those responsible to be held to account.

"Let me be clear – this method of warfare may be new and unfamiliar. But international humanitarian and human rights law apply regardless and must be upheld," Turk told the council. (Reuters)