Andal Ampatuan Jr wore a bulletproof vest as he appeared in court
The chief suspect in the massacre of 57 people in the southern Philippines - the country's worst political murder - has appeared in court in Manila.
Andal Ampatuan Jr wore a bulletproof vest and was accompanied by armed guards to attend the hearing.
He denies multiple charges of murder over last month's attack, which killed members of a rival political family and journalists travelling with them.
In court he was harangued by reporters angered by the deaths of colleagues.
The preliminary court hearing was to hear evidence and give Mr Ampatuan an opportunity to challenge the charges.
His lawyer, Sigfrid Fortun, waived his client's right to counter the charges because, he said, the Justice Department appeared to have already reached the conclusion that there was a case to answer.
'Seething with anger'
Esmael Mangudadatu, the candidate who planned to challenge the Ampatuans for the provincial governorship- and whose wife, sisters and other relatives were among those killed - attended the hearing.
Later he said he was "seething with anger" toward Mr Ampatuan.
Dozens of Filipino journalists, whose 30 colleagues were among those who died, jeered at him and pushed pictures of the victims' mutilated bodies in his face.
In total, about 160 people, including the suspect's father and other members of the powerful Ampatuan clan, are being investigated for involvement in the killing.
Troops and police have recovered hundreds of firearms at or near Ampatuan properties, including mortars and heavy machine guns, and enough ammunition for a battalion.
The Ampatuan clan have long controlled Maguindanao province and have been loyal supporters of President Gloria Arroyo.
Since the killings, Mr Ampatuan Jr, his father and his brother Zalday have been expelled from her party.