Caretaker Prime Minister Najib Mikati on Monday declared three days of national mourning over the death of Iran’s president Ebrahim Raisi, foreign minister Hossein Amir-Abdollahian and a number of officials in a helicopter crash.

According to Mikati’s memo, flags will be flown at half-mast at all public administrations and institutions while radio and TV programming will be adjusted to suit the situation.

Four Hezbollah fighters were killed Monday in south Lebanon, with the Iran-backed group announcing a retaliatory attack.

Hezbollah announced the deaths of the four fighters, two of them from al-Naqoura, "on the road to Jerusalem" -- the phrase used for fighters killed by Israel.

The head of Hezbollah’s parliamentary bloc, MP Mohammad Raad, said Sunday that his group is “reassured” over the course of its conflict with Israel.

“The resistance is escalating its operations against the Israeli enemy to a certain level in order to preserve the deterrence equation,” Raad said.

Hezbollah targeted Friday a logistic military base in the occupied Golan heights with 50 Katyusha rockets, in response to al-Najjariyeh strikes.

The group said in a statement it has attacked the Tznobar base in response to the killing of two civilians in a strike on al-Najjarieh, near the coastal city of Sidon.

Kataeb Party chief Sami Gemayel has accused Hezbollah of wanting to keep the Syrian refugee crisis unresolved in order to “pressure Europe and the West to free Syria of its isolation.”

“It is pressuring Lebanon to normalize relations with Syria and it is using Lebanon, the Lebanese people and the Syrian people present in Lebanon as a pressure card,” Gemayel added in a TV interview.

Former Progressive Socialist Party leader Walid Jumblat has noted that “Hezbollah is defending Lebanon,” while describing Israel as “Lebanon’s historic enemy.”

“When the war started in the south, I said that we should not get involved or that Hezbollah should not get implicated in the war, but the war started,” Jumblat said in an interview with the BBC.

Head of Hezbollah's executive council, Sayyed Hashem Safieddine, warned Israel on Friday that Hezbollah is ready to use new weapons in the battlefield.

Hezbollah has regularly fired missiles across the border with Israel over the past seven months, but has on Thursday launched its first successful missile airstrike from within Israeli airspace, using a drone that fired two missiles. The attack wounded three soldiers, one of them seriously, according to the Israeli military.

Israeli air strikes on Friday hit an area of southern Lebanon far from the border, with Hezbollah announcing one dead fighter and official media saying two Syrian children were killed.

The National News Agency said "Israeli strikes targeted Najjariyeh and Addousiyeh", two adjacent villages about 30 kilometres from the Israeli border just south of the coastal city of Sidon.

After more than 18 months of presidential void in Lebanon, the ambassadors of Egypt, France, Qatar, Saudi Arabia, and the United States reemphasized Thursday in a joint statement the dire situation facing the Lebanese people and the irreversible implications of delaying the crucial reforms on Lebanon’s economy and social stability. "Lebanon cannot afford to wait another month," they said.

"The country needs and deserves a president who unites the nation, prioritizes the well-being of its citizens, and forms a broad and inclusive coalition to restore political stability and implement necessary economic reforms. The election of a president is also needed to ensure that Lebanon has a seat at the table in regional discussions and to conclude a future diplomatic deal on Lebanon’s southern border," the statement said.

Caretaker Prime Minister Najib Mikati called for Israel's withdrawal from occupied Lebanese territories Thursday as he participated in an Arab League summit in Bahrain dominated by the Israel-Hamas war.

Mikati urged fellow heads of state and government at the 22-strong grouping in the capital Manama to "pressure Israel to withdraw from our occupied land and stop its violations and attacks on our land, sea and air."