MANILA: Al-Qaida-linked militants holding an Italian Red Cross worker captive killed five Philippine marines and wounded 10 others in an ambush Saturday on a southern island. One police officer was wounded.

About 40 militants attacked a group of marines and special operations police pursuing Abu Sayyaf gunmen holding 62-year-old Eugenio Vagni outside Parang township on Jolo island, said marines spokesman Lt. Col. Edgard Arevalo.

"They were treacherously fired upon," Arevalo said.

He said the militants, who attacked with high-powered firearms and grenades, also suffered an undetermined number of deaths.

There was no word on Vagni, who is suffering from hypertension and hernia. He marked his 150th day in captivity Saturday.

On Thursday, marines assaulted a militant stronghold near Indanan township close to Parang. Two marines and eight Abu Sayyaf militants were killed in that fighting, including two sons of Abu Sayyaf commander Abu Pula Jumdail and a son of another commander, Albader Parad.

Vagni was one of three International Committee of the Red Cross workers kidnapped on Jolo, an impoverished Muslim region 590 miles (950 kilometers) south of Manila, on Jan. 15. Abu Sayyaf militants have freed the two others — Filipino Mary Jean Lacaba and Swiss Andreas Notter.

In a statement Thursday, ICRC Asia-Pacific operations chief Alain Aeschlimann appealed to the kidnappers to release Vagni "safe and sound, unconditionally and without delay."

He said Vagni last called his wife on June 2.

"We are of course extremely concerned about Eugenio's safety and well-being. It is very upsetting and frustrating to admit that this crisis remains unresolved after almost five months," he said.

The Abu Sayyaf, which has about 400 fighters, is on the U.S. list of terrorist organizations because of its al-Qaida links and many terrorist attacks, including those that have victimized Americans.

The group and its allies have turned to kidnappings to make money in recent years, raising concerns among Philippine and U.S. security officials that ransom payments could revive the group, which has been weakened by years of U.S.-backed offensives.

It is believed to have raised more than $1.5 million last year through ransoms.