Weeks before a secret nighttime mission rescued more than 400 people from Syria, Canadian officials were behind the scenes helping to plot the dramatic escape.

Canada’s Head of Syria Political Affairs, Robin Wettlaufer, met with the leader of the White Helmets in early July. Recognized by their signature white headgear, the volunteer-led search-and-rescue organization has been nominated for the Nobel Peace Prize for their brave work providing medical aid to victims of the bloody civil war.

Syrian President Bashar al-Assad considers the group a personal enemy for their use of helmet-mounted cameras, which have captured horrific footage of bombings and chemical attacks. Assad has dubbed the group “agents” of foreign powers and accused them of staging footage.

Members of the White Helmets have been rounded up, thrown into detention facilities and tortured. By mid-summer, Assad’s forces were closing in on the group. To make matters worse, fighting between an ISIS-affiliated group and Russian-backed forces loyal to Assad were engaged in intense fighting.

The group’s only option was to escape Syria, but the mission was fraught with uncertainty. The border to neighbouring Jordan was closed off, and the only safe exit out would be through Israel.

So White Helmets leader Ra-ed Saleh reached out to Canada’s special envoy with a simple but desperate plea: Is there anything Canada could do to help?

Wettlaufer said it was clear that getting them out would be a harrowing operation, but that something needed to be done.

“This had about a two-per-cent chance of success. It was mission impossible,” Wettlaufer told journalist and filmmaker Sally Armstrong.

“There were so many reasons this couldn’t work. They were pinned between advancing regime and ISIS forces against two sealed international borders in one of the most geo-politically sensitive regions of the world.”

The unprecedented rescue was carried out on the evening of July 23, less than three weeks after the meeting. A coded message was sent to the White Helmets within Syria, telling them to make their way to the heavily guarded border between Israel and Syria.

Major Efi Ribner with the Israeli Defense Force remembers watching the nervous group approach the gate.

“You see, all of a sudden, people coming out of the dark towards the gate – frightened, nervous people. And then they very carefully approached the Israeli-Syrian border, not really knowing where to go or how to conduct themselves,” Ribner said.

Israeli defence forces, positioned at the Golan Heights, waited until the cover of dark to open the gates. Once inside, they were safe.

White Helmets Jihad Mahameed and Farouq Habib had previously crossed into Israel. They were stationed at the border with satellite phones that recorded the mission and kept officials in Israel and Canada in the loop.

“As soon as I saw the first person cross, I felt relief,” Mahameed said.

In total, 422 people -- a mix of White Helmets and their families - boarded 10 buses en route to Jordan. That’s less than the 700 people who were expected to make the crossing.

For many, the crossing was an emotional moment. Habib recalled watching a family make the final steps to safety.

“The mother was crying and the father started crying. And all of us, actually,” he said.

The precarious mission’s success is due, in large part, to Israel, said Deborah Lyons, Canada’s ambassador to Israel.

“Very much to their credit, the Israeli government and the Israeli military put human life ahead of politics and said, ‘We are there to help the White Helmets,’” Lyons said.

Following the rescue, the Canadian federal government committed to resettle up to 50 of the White Helmets and their families. However, because only 422 of 700 made the crossing, Canada is expected to take 20 to 30 families.

Germany, France and the United Kingdom have also committed to the resettlement efforts.

The group remains in Jordan where their applications for resettlement are being processed.

Following the rescue, Foreign Affairs Minister Chrystia Freeland hailed the White Helmets as “heroes.”

“The White Helmets are courageous volunteers and first responders who risk their lives to help their fellow Syrians who have been targeted by senseless violence,” Freeland said in a statement.

“When children, women, and men in Syria flee for their lives, the White Helmets run towards danger, towards the rubble, to save the innocent and the wounded.”

Stay tuned for tomorrow, when we’ll have a behind-the-scenes look at how the operation unfolded.

With a report from Sally Armstrong for CTV News