KATMANDU, Nepal—When Yehezkel Lifshitz, the rabbi at a Jewish community center in the Nepali capital, answered the phone on the afternoon of Oct. 14, he got an urgent message that helped set in motion an extraordinary, improvised rescue effort for hundreds caught by the ferocious blizzard that battered northern Nepal last week.

Israeli diplomats had also got word that the storm had trapped a group of Israeli hikers high in the Himalayas. They called local officials in the storm-hit area and alerted other embassies, while Rabbi Lifshitz at Chabad House phoned trekking agencies and others who could help.

Before long, Nepal’s armed forces and police, diplomats of many nationalities, Nepali villagers and mountain-guiding and helicopter companies were drawn into a largely ad hoc search for those who survived the storm, and those who didn’t.

By Monday, hundreds of people—between 200 and 250 of them Israelis, according to the Israeli Embassy—had been brought to safety. Nepal’s Home Ministry put the death toll at 33, including four Israelis.

For many Israeli travelers, the rescue started with a hand-delivered letter dispatched that Tuesday by a group of Israelis who had climbed through pummeling wind and snow to seek shelter in a wooden shack.