JERUSALEM — The Israeli army attacked a Hamas military base in the northern Gaza Strip after a group of Palestinians entered Israel and planted two bombs along the border fence.

The airstrikes were carried out early Monday morning, according to the Israel Defense Forces. Several hours earlier, the IDF said, three men entered Israel from Gaza and planted the two improvised explosive devices – plastic bottles filled with an ignitable liquid and a detonator — before returning to Gaza. Their actions were captured on closed circuit surveillance cameras. Israeli troops located the bombs and removed them.

“The IDF views with great severity any attempt to damage the security fence or security infrastructure and will not allow the region to become a combat zone,” the IDF spokesman said in a statement.

The incident comes as Palestinians in Gaza continue the March of Return protests, six weeks of demonstrations scheduled to end in mid-May on the 70th anniversary of the founding of the State of Israel, which the Arab world calls the Nakba, or catastrophe.