State media also reported "heavy gunfire" accompanying the start of the 10-day truce, announced earlier by US President Donald Trump.

AFP journalists heard shots ring out and RPGs erupting into the air shortly after midnight and continuing for well over half an hour, as red bullet traces took off into the sky.

AFPTV footage showed people returning to the city's southern suburbs, a Hezbollah stronghold, some waving the Iran-backed movement's yellow flag or carrying portraits of its slain leader Hassan Nasrallah, killed by Israel in 2024.

Videos circulating on social media showed queues of cars in several areas in the south as displaced residents returned to their homes.

Lebanese authorities say the war has displaced more than one million people.

Hezbollah earlier on Thursday called on Lebanese residents to postpone their return to the country's south, the Bekaa valley, and Beirut's southern suburbs, "until the situation becomes completely clear".

The Hezbollah-affiliated Islamic Health Committee, in a statement, also advised people to wait "until you are certain that a ceasefire has been officially declared and has come into effect" and urged people to "wait until morning" before taking to the roads.

The army command also called on citizens to heed instructions of Lebanese soldiers deployed in the south, where Israeli troops have invaded across the border, and to beware of unexploded ordnance and "suspicious objects".

No Israeli airstrikes were reported in the hour after the ceasefire came into effect.

Lebanese state media said, however, that "despite the passage of about half an hour after the ceasefire came into effect, the artillery of the enemy Israeli army is still shelling the towns of Khiam and Debbine, in conjunction with combing operations with machine guns in the area."