Israel’s leaders commemorated Memorial Day on Monday, a usually somber holiday that this year was almost entirely absorbed by the ongoing war in Gaza.

At 11:00 A.M., sirens announced two minutes of silence, and a formation of four fighter planes then flew over Jerusalem and the surrounding areas. At a ceremony, Israeli Prime Minister Benjamin Netanyahu vowed once again to defeat Hamas, a promise he has made repeatedly during Israel’s brutal seven month war with the militant group.

Some 300,000 Palestinians fled Rafah over the weekend as Israeli forces pushed deeper into the southern city, according to U.N. estimates.

Israel says Rafah is the last stronghold of the Hamas militant group and vowed to launch a full-scale invasion of the city, but the U.S. says a Rafah offensive would jeopardize cease-fire talks and threatened to halt more military aid to Israel. Some 1.4 million Palestinians — over half Gaza’s population — had sought refuge in the city.