Netanyahu: Israel will do 'whatever is necessary' to protect Israelis from terrorist attacks

WASHINGTON - Israeli Prime Minister Benjamin Netanyahu says his government has "fully substantiated intelligence" that Wednesday's attack against Israeli tourists in Bulgaria was carried out by the Iran-backed Lebanese militant group Hezbollah.

Netanyahu tells CBS' "Face the Nation" that Israel "will do whatever is necessary" to protect innocent Israelis and says "there has to be a price exacted" from the terrorists and their backers.

Iran has denied responsibility for the bombing, which killed five vacationing Israelis, along with a Bulgarian bus driver and the attacker.

Netanyahu won't discuss specifics of a response, but the attack threatens to escalate a shadow war between Israeli and Iran over allegations that Iran is trying to build nuclear weapons. Iran says its atomic program is for peaceful purposes only.