At least two U.N. peacekeepers were wounded in south Lebanon after Israeli forces deliberately fired tank shells at the UNIFIL headquarters there Thursday.

The attack was one of three cases in the last 24 hours of peacekeeping force's positions targeted by Israel, U.N. sources said.

"This morning, two peacekeepers were injured after an IDF Merkava tank fired its weapon toward an observation tower at UNIFIL's headquarters in Naqura, directly hitting it and causing them to fall," the force said, using an acronym for the Israeli military.

"The injuries are fortunately, this time, not serious, but they remain in hospital," it said, adding that "UNIFIL's Naqura headquarters and nearby positions have been repeatedly hit."

According to UNIFIL, the Israeli military also hit another position in Ras Naqura on Thursday.

The peacekeeping force said it hit "the entrance to the bunker where peacekeepers were sheltering and damaging vehicles and a communications system."

"An IDF drone was observed flying inside the UN position up to the bunker entrance," it said.

UNIFIL, which has some 10,000 peacekeepers stationed in south Lebanon, has called for a cease-fire since an escalation between Israel and Hezbollah on Sept. 23.

On Wednesday, "IDF soldiers deliberately fired at and disabled the position's perimeter-monitoring cameras," it added.

"They also deliberately fired on (a site) where regular tripartite meetings were held before the conflict began, damaging lighting and a relay station."

"We remind the IDF and all actors of their obligations to ensure the safety and security of U.N. personnel and property and to respect the inviolability of U.N. premises at all times," it said.