Two Philippine hostages beheaded

The Abu Sayyaf has carried out a series of high-profile kidnappings for ransom in recent years

JOLO, Philippines (CNN) -- Al Qaeda-linked Muslim extremists have beheaded two men abducted from the remote southern island of Jolo, the Philippine military says.

Military officials reported finding two male heads on Jolo Thursday. They were believed to be those of hostages taken by Abu Sayyaf guerrillas on Tuesday, said Brigadier Gen. Romeo Tolentino, the army commander for the Philippine military.

Jolo is about 560 miles (900 kilometers) south of the capital, Manila.

Tolentino told CNN the men were warned not to venture into the remote area, but they did so anyway.

The Abu Sayyaf group is suspected of terrorist activities in the area and has been a target of military forces since last year.

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It was originally reported that five men and three women were taken hostage Tuesday afternoon by one or two kidnappers but on Wednesday, Gen. Tolentino said the hostages included four women and four men.

Authorities had also believed the group was mainly comprised of cosmetics sales agents but according to Reuters news agency Tolentino said they had been wrongly identified and were Jehovah's Witnesses.

"They are showing their crusade not to allow Christians to enter their community," Tolentino said of the killings. Two other hostages -- both Muslims -- were earlier freed but the four women are still in captivity, he added.

Both the dead have been identified by their families, he said.

Jolo is known as a stronghold of the Abu Sayyaf -- a militant group that has a history of kidnapping for ransom and has been linked to Osama bin Laden's al Qaeda terror network.

In April 2000, 21 people -- 10 tourists and 11 resort workers -- were kidnapped from a Malaysian diving resort by Abu Sayyaf gunmen and taken to Jolo.

All but one were eventually released after ransom was paid.

Offensive

The latest kidnappings are the first carried out by the group since some 1,200 American troops arrived in the southern Philippines in January to aid a military offensive against the militants.

The majority of U.S. Special Forces deployed to the area left about three weeks ago, although several hundred troops remain on the nearby island of Basilan carrying out infrastructure projects and medical assistance.

In June this year, Philippine troops trained by U.S. advisors stormed an Abu Sayyaf jungle camp in an effort to rescue two Americans and a Filipino nurse being held hostage by the group.

The nurse and one of the Americans was killed in the rescue attempt, although the other hostage, U.S. missionary Gracia Burnham escaped with only minor injuries.

Since then the Philippine government, led by President Gloria Macapagal Arroyo, has vowed an all-out effort to crush the Abu Sayyaf.