An American woman who was kidnapped by the same terror group that killed Canadian John Ridsdel says a rescue mission may be the only way to save the three remaining hostages -- even though it couldn’t save her husband.

“If (Canada) has got some guys who know what they’re doing on the battlefield, it might be a good idea to go get that guy out of there,” said Gracia Burnham, a U.S. missionary who was held by Abu Sayyaf for more than a year.

Burnham and her husband Martin were celebrating their 18th wedding anniversary at an island resort in Palawan, Philippines, in 2001, when they were kidnapped along with two others.

Burnham said they were marched around the jungle, suffering dysentery from dirty river water, and wondering if they would ever see their families again. They would go without food for 10 days at a time.

There were constant ups and downs. At one point, a ransom was paid. “We were so happy when someone paid a ransom for us,” she said.

But it didn’t work. Abu Sayyaf demanded more.

Early on, the captors led away Peruvian-American hostage Guillermo Sobero and killed him. The Burnhams were told they had “released him without his head.”

Canadian John Ridsdel was also beheaded, after a deadline for a ransom demand came and went on Monday. He was kidnapped in September -- also from an island resort -- with Canadian Robert Hall, Norwegian Kjartan Sekkingstad and Filipino Marites Flor, who are believed to be still alive.

Burnham didn’t know it at the time, but the Filipino military had attached a tracking device to one of the militants, a group whose numbers dwindled from about 80 to only 14 by the time the army moved in, a little over a year after they were captured.

Filipino soldiers came running over a mountain, guns blazing. “My husband and I were immediately shot -- me in the leg, him in the chest,” she recalled. “Leg wounds heal, chest wounds don’t,” she said. Martin died quickly.

Burnham said she doesn’t know who fired the fatal shot, but added “a lot of soldiers lost their lives trying to rescue us, so I would never blame the military for anything that happened.”

Still, she said “what we really wanted was the American Armed Forces, the special agents, to come in with their night vision goggles and just get us out of there.”

“Some well-placed Navy Seals could have got us out,” she said. “But that wouldn’t have worked politically. The Philippines, because of their sovereignty, wouldn’t let the Americans fight on their soil.”

Experts seems to agree a Canadian army rescue mission is unlikely, and for the same reason.

"I don't think there is anything that you're able to do other than help the police and the forces of the sovereign state involved," Retired Brig.-Gen. James Cox told The Canadian Press earlier this week.

Security expert Larry Busch told CTV News Channel Tuesday that Canadians should not expect to see any Canadian special forces or RCMP on the ground in the jungle, in part because of Philippine sovereignty.

However, he said Canadian experts may be on the ground, perhaps in Manila, helping to plan such an operation.

“I think the Philippine government is quite capable of carrying this out,” Busch added.

Former Ontario Premier Bob Rae told CTV’s Power Play last week that negotiations had been under way to free Ridsdel and the three other hostages.

“Obviously there was talk of money involved, not by the Government of Canada or the Government of Norway, but certainly by the families,” Rae said.

Prime Minister Justin Trudeau said forcefully Tuesday that “Canada does not and will not pay ransom to terrorists, directly or indirectly.”

Burnham believes that a ransom probably wouldn’t work anyway. “When you’re negotiating with bad guys,” she said, “they’re not going to keep their word.”

With a report from CTV News Senior Political Correspondent Glen McGregor