Troops close in on extremists holding American couple

ZAMBOANGA, Philippines -- Government troops said Tuesday they trapped a unit of Muslim extremist rebels holding two American missionaries in dense jungle and appealed to them to surrender.

Col. Francisco Gudani said his men while fighting could see the Abu Sayyaf rebels holding Wichita, Kan., missionaries Martin and Gracia Burnham on the southern island of Basilan.

At least 11 guerrillas were killed and two soldiers were wounded in the fighting, military officials said.

"There is heavy fighting right now in Basilan and we have visual contact with the enemies," Gudani said. "The Burnham couple are with the gunmen whom soldiers are now fighting in the hinterlands."

The Abu Sayyaf rebels hold at least 10 Filipino hostages, mostly workers seized from coconut plantations, but the military did not know whether any were with the unit attacked Tuesday.

The fighting comes a day after the Abu Sayyaf threatened to behead the Burnhams if the military does not stop its assault.

Gudani said the Abu Sayyaf are under increasing pressure.