The US has filed murder charges against five rebel leaders of the Philippines' Abu Sayyaf guerrilla movement for the kidnap and murder of US nationals.

The five indictees

Khadafi Abubakar Janjalani Isnilon Totoni Hapilon Aldam Tilao Jainal Antel Sali Jr Hamsiraji Marusi Sali

Federal charges were filed for the murders of missionary Martin Burnham and Peruvian-born Guillermo Sobero, Deputy Attorney General Larry Thompson said.

Also included were charges relating to the kidnapping of Mr Burnham's wife, Gracia Burnham, who was rescued on 7 June.

The five include Khadafi Abubakar Janjalani, believed to be the spiritual leader of the group and Isnilon Totoni Hapilon, said to be the second in command.

"The United States sends a signal - we will work to track down and prosecute all those who commit barbaric acts of terrorism here at home and abroad," Mr Thompson said.

The indictments come a month after the leader of the group, who went by the name Abu Sabaya, was believed killed during a gun battle at sea with US-trained Philippine troops.

Reign of terror

Hostage-taking is the Abu Sayyaf's main activity although its stated aim is the creation of an independent Muslim state in the south of the mainly Christian Philippines.

In June, Mr Burnham was killed during a military rescue mission, along with nurse Ediborah Yap and three of the guerrillas.

Mrs Burnham was wounded with a gunshot to the thigh and has since returned to the US.

The couple had been held captive for more than a year.

The US links the group to Osama Bin Laden's al-Qaeda network and US troops have been training Philippines forces to combat the rebels.

About 200 guerrillas are believed to still hiding out on the mainly Muslim southern islands of Basilan and Jolo.