Israeli troops fought fierce battles with Hezbollah fighters on Friday in different areas in south Lebanon, including a coastal town that is home to the headquarters of U.N. peacekeepers.

A spokesman for the U.N. peacekeeping force known as UNIFIL told The Associated Press that they are monitoring “heavy clashes” in the coastal town of Naqoura and the village of Shamaa to the northeast.

Israel has told U.S. mediator Amos Hochstein that it rejects France's participation in the monitoring committee that will supervise any ceasefire agreement with Lebanon, Arab and Israeli media reports said on Friday.

Legendary Arab singer Fairouz, whose ballads have told of love, her native Lebanon and the Palestinian cause, turned 90 on Thursday as her conflict-weary country is wracked by the Israel-Hezbollah war.

Strikes hit the southern suburbs of Beirut shortly after an Israeli evacuation warning early on Friday, according to Lebanese official media and AFPTV footage.

The Israeli military has launched an investigation into the death of a 70-year-old Israeli man who entered Lebanon with Israeli forces and was killed in a Hezbollah ambush.

Investigators are trying to determine, among other things, who allowed Zeev Erlich into the combat zone with the forces and why he was permitted to enter.

Israeli strikes killed at least 51 people on Thursday in towns and villages across Lebanon, according to the country's Health Ministry.

In eastern Lebanon, intensified Israeli airstrikes killed 40 people in 10 different towns in Baalbek province, the ministry said. Rescuers were searching under the rubble of destroyed buildings, said Gov. Bachir Khodr, calling it “a very violent day” in his province.

Significant progress has been made towards a ceasefire agreement between Lebanon and Israel, but there are still some gaps to be closed, Israeli and U.S. officials told U.S. news portal Axios on Thursday.

Lebanon's health ministry said Israeli strikes on several locations in the eastern Bekaa Valley killed 22 people on Thursday, with state media reporting four family members killed in one village.

"Israeli enemy" strikes on five areas in the Baalbek region killed a total of 22 people, the ministry said in separate statements, with the National News Agency reporting that a strike on the village of Maqneh killed at least four members of the same family.

Hezbollah on Thursday claimed seven attacks on Israeli soldiers in and near south Lebanon’s Khiam, after official media said Israel troops were dynamiting homes and buildings in the town.

In seven separate statements, Hezbollah said its fighters targeted Israeli troops in and near Khiam, including with artillery, rockets and drones, as Lebanon’s National News Agency said "the enemy army" was "blowing up homes and residential buildings during its incursion into the town".

Israel’s failure to tamp down Hezbollah’s short-range rocket threat has put pressure on its government to embrace a cease-fire, the New York Times has reported.