The annual official memorial ceremony for Israel’s fallen soldiers whose final resting place is unknown was held on Sunday at the Mount Herzl Military Cemetery in Jerusalem. The families of the soldiers laid wreaths at the monument in memory of their loved ones.

As of May 2012, just under 23,000 Israelis had been killed in action since 1948 — with 181 of them never being afforded a proper burial. One-hundred-and-eight of the soldiers without a known grave were killed during Israel’s War of Independence in 1948.

Over the years some of the bodies were found and buried, while others were discovered and left untouched — as was the case with the 68 crew members of the Dakar submarine, the remains of which were found in 1999, more than 30 years after it had disappeared.

The annual remembrance day takes place on the seventh day of the Hebrew month of Adar; according to Jewish tradition, this is the day the prophet Moses died, and was buried by God in an unknown location.