Hezbollah’s deadly attack against an army base deep inside Israeli territory presents a major headache for Israel as it continues to struggle to defuse the threat posed by the group.

A Hezbollah-fired drone that killed at least four Israeli soldiers is the latest incident of an UAV bypassing the country's air defense systems.

Hezbollah said the drone attack was in retaliation for two Israeli strikes in Beirut on Thursday that killed 22 people.