Yoav Halper’s phone rang on the worst Saturday morning of his life with a call that he was expecting.

It was a few hours after Hamas attacked Israel on Oct. 7 when Halper first heard from his contacts at Magen David Adom, the country’s national ambulance and paramedic organization. They needed as many ambulances as they could get as fast as they could get them—and they knew just the person to call.