You may not know their names, but you know the work they do.

As chaos reigns after a terrorist attack in Israel, they are the yellow-jacketed workers swooping in, saving lives, scouring the crime scene and retrieving body parts, right down to the last drop of blood.

They are volunteers with Zaka Rescue and Recovery, Israel’s national network of emergency aid workers. Trained as paramedics, most —but not all — belong to fervently religious sects for whom their grim task fulfills halachic dictates.

But their work cuts across all sectarian and ethnic lines. Even suicide bombers’ bodies and blood are meticulously collected.

“It’s a hard job,” says Matis Zahav, executive director of Zaka, who has had up-close-and-personal experience with terror. “About two years ago, I was driving behind a bus on French Hill [in Jerusalem] when I saw it explode. A little girl died in my arms.”

Zaka’s work didn’t end with the little girl’s death. Volunteers contacted the family and provided subsequent grief counseling as well.

Talia Zaks, a Zaka administrator, normally doesn’t go out on emergency calls, but living in Israel during the current matsav (Hebrew for “situation”), no one is immune to the risks. Riding along with Zaka workers last summer on Jerusalem’s Jaffa Street, Zaks found herself a few hundred feet behind bus No. 14 when it, too, blew up.

“I couldn’t move,” she remembers today with obvious pain. “Everywhere was the smell of burning, everything broken, the sounds of sirens and shouting. That was what hell looks like.”

Fortunately her colleagues, prepared for such horrors, grabbed their equipment from the backseat: first aid kits, oxygen, bags, gloves and other accoutrements of mercy.

“At that moment,” she says, “I fully realized what our volunteers do.”

That could best be described as chesed shel emet, a Hebrew expression meaning “true mercy,” and by extension, “respecting the dead.”

And virtually everyone in Israel recognizes the importance of the work. That’s why Zaka is one of the relatively few institutions in the country in which both the religious and secular work together side by side.

As an unofficial adjunct of the Israeli army, Zaka makes sure its volunteers are in top form. Ninety percent of them are professional paramedics trained by Magen David Adom, the country’s official EMT response team, and by the Israel Defense Forces.

They are also well equipped. Zaka maintains a fleet of 25 ambulances (including an armored vehicle), and Zahav is especially proud of Zaka’s custom-designed motorcycles.

Of course, custom-built motorcycles don’t come cheap, but Zaka has managed to survive entirely on donations. With 940 unpaid volunteers fanned out across the country, Zaka maintains a paid staff of only 18.

But its work has drawn worldwide attention, inspiring one British member of Parliament to nominate Zaka for a Nobel Peace Prize.

Instead, Zaka workers will settle for simply going out of business on the day peace breaks out.

“We always say we hope we use our ambulances only to bring pregnant women to the hospital,” says Zaks wistfully. “But what we do is holy work, and I feel privileged to do it.”

Dan Pine accompanied the S.F.-based Jewish Community Federation’s Israel and overseas committee on a recent trip to Israel.