The Lebanese health ministry said that Israeli strikes on Sunday killed at least 21 people across southern Lebanon.
Nine people were killed and 38 wounded in a strike on Haret Saida, near the port city of Sidon, the ministry said. At least seven others including a nurse and three rescuers were killed in the southern village of Ain Baal and five in Burj al-Shemali.
A strike on Haret Saida, about 60 kilometers (37 miles) from the Israeli border, completely destroyed the top floor of a three-story building, according to an AFP correspondent.
Nearby buildings were also damaged. The Lebanese army blocked access to the sector, which has become crowded with people fleeing other areas of south Lebanon since Israel launched its offensive against Hezbollah in September.
AFP's correspondent said that no warning to evacuate the zone was given before Israel's strike.
In Ain Baal, the dead included three emergency workers working at a center run by the Al-Riossala Association, a charity linked to the Shiite political party Amal, which is an ally of Hezbollah.