Eloise Bergen is shown with a child in Kenya in this recent handout photo. (Canadian Press)

Two Canadian missionaries are in critical condition at a Kenyan hospital after robbers armed with clubs and machetes beat them inside their home, the head of the Christian charity the couple worked for told CBC News.

John Bergen, 70, of Vernon, B.C., and his 66-year-old wife, Eloise, suffered deep slashes on their heads and faces after as many as five men invaded their residence in the Mount Elgon region of western Kenya, said Ralph Bromley, president of the Kelowna, B.C.,-based Hope for the Nations.

Bergen underwent three hours of surgery at a Nairobi hospital to treat his injuries, which include multiple fractures to the head, jaw and skull, Bromley said Thursday. Bergen also has broken bones in his arms, knees and legs.

"He was an absolute mess. Cut from head to toe. On top of that, multiple fractures," Bromley said from B.C.

His wife, who is from the U.S. state of Georgia, was tied up during the overnight invasion of their home, which was secured with a fence and a guard.

"They're both severely traumatized," Bromley told CBC News.

The couple was airlifted to Nairobi for treatment by bone specialists. Two of the couple's guards, as well as five others, have been arrested, according to another of the group's volunteers, Steven Pippin. Four other suspects are still on the lam.

Bromley said gang members came through the gate of the couple's home, took out the security guard and attacked John Bergen with knives, machetes and clubs.

"They threw him into the bushes, left him for dead and went in and tied up Eloise and assaulted her. When they were finished with that assault, they threw the bed on top of her, they threw the furniture, and they left the compound," Bromley said.

Eloise Bergen was able to free herself after she found a pair of scissors and was able to load her husband into a vehicle. She drove through the gate of their compound because she was unsure whether the men were still chasing them, Bromley said, and continued on to the charity's headquarters.

"They come through their gate after the assault, and they were totally covered in blood and you can imagine how it traumatized our staff," Bromley said.

He said money seems, so far, to be the motivating factor for the assault.

"What we don’t understand is why the vicious attack that went with the theft," he said.

'Senseless act of violence'

The couple arrived in the country in March following the east African nation's political crisis to set up a school and perform development work in the community, Bromley said. It was their first trip with the charity, which works to help children at risk around the world.

"When a foreigner is attacked, it brings a cloud over the nation, especially after what Kenya has just been through," he said.

The couple's daughter-in-law, Robyn McGough of Calgary, said the couple's four children had been worried because their parents were working in a war-torn country.

"When I heard about it my stomach was empty and I just said 'I knew it, I knew it.' I hated them going," she said.

Foreign Affairs spokesman Alain Cacchione called the attack a "senseless act of violence" and said consular officials have been in contact with the couple and are providing assistance.

He said the Canadian officials were also in contact with local police to ensure the investigation moves rapidly toward apprehending the assailants.

McGough said the family needs the federal government's help to bring the couple home — the cost to fly John alone is expected to cost at least $150,000 with medical assistance. She said the family is appealing to the public for donations.

In the meantime, one son and a grandson are expected to fly to Kenya this weekend.

With files from Canadian Press