JERUSALEM: Israel accused the Iranian-backed Lebanese militia Hezbollah on Wednesday of conducting a cyber operation designed to disrupt a U.N. peacekeeping mission on the border between the countries, and threatened harsh Israeli retaliation against enemy hackers.

The allegation - to which there was no immediate response from Hezbollah or Tehran - came as Israeli-Iranian tensions soar.

In what he termed a first public disclosure of the incident, Israeli Defence Minister Benny Gantz said “Iranian security institutions in cooperation with Hezbollah (recently) launched a cyber operation with the aim of stealing materials about UNIFIL activities and deployment in the area, for Hezbollah’s use”.

“This is yet another direct attack by Iran and Hezbollah on Lebanese citizens and on Lebanon’s stability,” he told a cyber conference at Tel Aviv University, without elaborating.

UNIFIL said it was the first it had heard of the attacks.

“UNIFIL and the UN take cybersecurity very seriously and have robust measures in place to protect our data. We are aware of media reports of comments by the Israeli defence minister today but we have not received any direct information on the alleged incident,” its media office told Reuters.

Established in 1978, UNIFIL patrols Lebanon’s southern border. It is charged with monitoring the ceasefire that ended the last war between Hezbollah and Israel in 2006.

Israel has accused Hezbollah gunmen of setting up clandestine positions at the border in defiance of UNIFIL. Lebanese officials say Israel continues air force overflights of their territory in violation of the ceasefire.

Gantz said an Iranian Revolutionary Guards Corps cyber unit called “Shahid Kaveh” had “conducted research to damage ships, gas stations and industrial plants in several Western countries including Britain, the U.S., France and Israel”.

Britain’s Sky News reported similar allegations last year, saying the Iranian embassy in London had not responded to them.

Gantz hinted that Israel - which is widely believed to have waged cyber war against Iran’s nuclear facilities and other infrastructure - may retaliate physically against enemy hackers.

“We know who they are, we target them and those who direct them. They are in our sights as we speak - and not just in the cyber-space,” he said. “There is a variety of possible responses to cyber-attacks - in and outside of the cyber-domain.”