'We urge the Government of the Philippines to take immediate steps to conduct full and impartial investigations into each case,' Amnesty International said, adding that 'witnesses, relatives and others involved in the investigations should be protected from intimidation and reprisals'.

'The results of the investigations must be made public and those found responsible for the killings should be brought to justice,' the international human rights organisation stressed.

In April, Benjaline Hernandez, Vice-President for Mindanao of the College Editors' Guild of the Philippines and Deputy Secretary General of the Southern Mindanao office of the human rights organisation Karapatan was killed along with three companions while undertaking research in the Arakan Valley. In May, Edgar Damalerio, a commentator on dxKP radio in Pagadian City, and managing editor of the Zamboanga Scribe was shot and killed while driving home from work. He had been known for producing articles about official corruption in the area.

In August, Sonny Alcantara, a TV presenter and editor of local newspaper Kokus, shot in the head and killed while riding his motorcycle in San Pablo City. He had written articles criticising the city's former mayor.

'In none of these cases have the results of investigations been made public. Nor have any perpetrators been brought to justice,' Amnesty International said.

In the case of Edgar Damalerio two witnesses have been subsequently killed and his family continues to receive threats despite having left Pagadian City out of fear for their safety.

Despite the existence in the Philippines of constitutional and legal safeguards designed to protect human rights and ensure a fair trial, Amnesty International is gravely concerned that a climate of impunity appears to persist today.

'Concrete measures must be taken to tackle impunity and to ensure that all those responsible for these killings (including those to have carried out the killings and, if applicable, those who have ordered them) are held accountable through the justice system,' the organisation said.

'In order to combat impunity and to prevent further human rights violations from occurring it is imperative that the government makes clear that justice applies to all and that perpetrators will be prosecuted regardless of the position or influence they hold,' the organisation added.

Background

The Philippines is known within the region for its vibrant press and yet is paradoxically a very dangerous place for journalists to work. At least eight journalists have been reported killed since 2000 and there have also been numerous reports of physical attacks and intimidation.

The deaths of Benjaline Hernandez, Edgar Damalerio and Sonny Alcantara appear to form part of a pattern of unsolved violence against journalists. The Overseas Press Club of America has reported that 38 journalists have been killed since 1986 and that no perpetrators have been convicted in these cases.