After seeing a television video of missionaries Martin and Gracia Burnham, who were kidnapped by Muslim Abu Sayyaf guerrillas from a resort in the Philippines in May, Gracia Burnham's sister, Mary Jones, said they were clearly suffering.
"I'd like to see the United States get more involved in assisting the Philippines in getting my sister out," Jones said on CBS News' "The Early Show."
"Six months is a terribly long time for them to be in this condition and anyone that sees the video can clearly see that they are suffering; that they are in terrible condition. If you know my sister and brother-in-law, you can barely even recognize them. It's very sad. We would like to see more done and we want them out soon."
The couple from Wichita, Kan., were interviewed Sunday while in captivity on the southern island of Basilan, according to freelance journalist Arlene de la Cruz, and a video of the interview aired on Philippines television Monday.
While Gracia Burnham voiced fear of dying in captivity and spoke of chest pains, her husband spoke of his determination to return home with her.
Abu Sayyaf leader Abu Sabaya said during the interview his group was "willing to negotiate" the release of their captives but that they preferred to die fighting than surrender.
Martin Burnham's mother, Oreta, said she was saddened to see how much her son and daughter-in-law were suffering but did not support paying a ransom for their release.
"I think there are other means that they can use to get them out safely," she said.
She also questioned how much officials were doing in their hunt for the kidnappers. "We really don't know what is being done, but we are concerned that they are not getting out. We'd like to see more done."
"It really bothers and concerns us that when they said they were surrounded and no one could get in and out. And then to find that someone could go right straight to where they were " she said.
The United States has linked the Abu Sayyaf to Islamic militant bin Laden and his al Qaeda network, prime suspects in the Sept. 11 air attacks on the United States.
The group claims to fight for an Islamic state in the south of the mainly Catholic Philippines but pursues kidnap for ransom as its main activity.
A third American taken hostage with the couple, Californian tourist Guillermo Sobero, was beheaded by the group in June.
The Burnhams, who have three children, have been based in the Philippines for 15 years. They were kidnapped while celebrating their 18th wedding anniversary.
Philippines soldiers captured two members of the Abu Sayyaf Sunay near Isabela City on Basilan island as government forces continued to scour the island for the captives.
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