In at least two border areas in southern Lebanon, the Israeli army opened fire on residents who tried to return to their villages, according to the Health Department, which says that the "aggression" took place in the villages of Houla and Kfar Kila.
In the attacks, 22 people were killed, according to reports on Sunday afternoon. Over 120 people are reported to have been injured. One of those killed was a Lebanese soldier, according to the country's army.
Late on Sunday evening, the US announced that the ceasefire agreement in Lebanon has been extended.
"The agreement between Lebanon and Israel, overseen by the US, will continue until February 18," the White House wrote in a brief statement.
The Israeli forces were originally supposed to withdraw on Sunday in accordance with the ceasefire agreement with Hezbollah.
Carrying Hezbollah flags
Demonstrators, some of whom carried Hezbollah flags, tried to enter several villages in the border area to protest against Israel's failure to withdraw its troops from southern Lebanon.
"Lebanon's sovereignty and territorial integrity are not negotiable," says Lebanese President Joseph Aoun in a statement.
He urges the people to "exercise self-restraint and trust in the Lebanese armed forces."
Israel's military spokesperson in Arabic, Avichay Adraee, claims that it is Hezbollah that is sending "insurgents" to southern Lebanon.
UN: Not a safe area
Israel is not commenting on the death toll, but says it "fired warning shots in several places" in southern Lebanon, reports the British BBC.
The Lebanese army has, together with the UN peacekeeping forces, gradually increased its presence in the southern parts of the country, as the Israeli military troops have gradually withdrawn.
Despite this, the area is still not safe for return, according to the UN:
"As we tragically saw this morning, the conditions are still not in place for the citizens to safely return to their villages along the blue line," says Jeanine Hennis-Plasschaert, the UN's special coordinator for Lebanon, in a joint statement with the head of the UN peacekeeping forces.
Israel announced on Friday that the withdrawal would be delayed. The reason was a delay in the deployment of Lebanese government soldiers in southern Lebanon. It also claims that Hezbollah has not withdrawn sufficiently from the border region.
The Israeli military (IDF) has forbidden residents from returning to several villages in southern Lebanon, but despite this, hundreds of Lebanese are trying to return to areas where the IDF is present.