An overnight Israeli strike on Iran killed Esmail Khatib, the intelligence minister, according to the Israeli defense minister.

Israel Katz, the defense minister, said Wednesday that Khatib had been in charge of "the regime's internal murder and repression system in Iran and of promoting external threats."

Announcing this latest killing, Katz said that "significant surprises are expected in all arenas" which will escalate the war against Iran and Hezbollah in Lebanon, without disclosing details.

-ABC News' Somayeh Malekian and Jordana Miller

At least six people were killed and 24 others were injured in early morning Israeli strikes on Beirut, the Lebanese health ministry said, as Israel said it struck Hezbollah-related infrastructure in both the capital and the country's south.

The Lebanese ministry said Beirut had been strike twice on Wednesday morning. At least one building in the city was levelled.

The Israel Defense Forces said in a statement that Hezbollah, the Iranian proxy operating in Lebanon, had fired "dozens" of rockets toward Israel.

The IDF said it responded to those rockets by warning residents of Tyre, a southern coastal city, of impending strikes. Strikes on the city then destroyed what Israel described as a weapons-storage facility.

Israel said it also targeted in Beirut "additional assets" of the Al-Qard Al-Hassan Association, a group said to help finance Hezbollah’s operations.

"Alongside headquarters of the 'Hamasin' Division in southern Lebanon that were struck from the air and sea, the Navy struck a key terrorist in the Hezbollah terror organization in Beirut," the IDF said in a statement early on Wednesday. "Prior to the strike, steps were taken to minimize the chance of harm to civilians, including advance warnings, use of precision munitions, and aerial observations."

Israel said its military intends to "continue to act forcefully against the Hezbollah terror organization, which decided to join the campaign and operate under the auspices of the Iranian terror regime, and will not allow harm to civilians of the State of Israel."

Officials in Saudi Arabia, Qatar, Kuwait and the United Arab Emirates said early on Wednesday they were working to intercept Iranian drones or missiles.

"Kuwaiti air defense systems are currently engaged in intercepting hostile missiles and drones that breached the country's airspace," the official Kuwait News Agency said.

The UAE was responding to incoming missile and drone threats from Iran, officials there said, adding, "MOD asserts that the sounds heard are the result of the Air Defense Systems intercepting missiles and drones."

Qatar said it was countering a missile attack. The Saudi Ministry of Defense said in a series of updates that it was attempting to down hostile drones, several of which were aimed at its Eastern Province, where much of the country’s oil production takes place.

U.S. aircraft dropped "multiple 5,000-pound deep penetrator munitions" on hardened Iranian missile sites along Iran’s coastline by the Strait of Hormuz on Tuesday, U.S. Central Command announced.

The bombs are officially “bunker busters” designed to strike at reinforced targets and can also penetrate deep towards a target. Their use against hardened Iranian missile targets along the Strait of Hormuz is part of the ongoing effort to prevent Iran from striking at commercial shipping through the strait.

Many of the larger bombs the U.S. has been dropping are 2,000-pound bombs.

A bomb, known as the Massive Ordnance Penetrator, a 30,000-pound bomb specifically designed to strike at deep underground facilities, was used last June to strike at Iran’s underground nuclear facilities.