Twenty-four people in the Philippines have been charged with rebellion after 57 people were massacred on the island of Mindanao last month.
Those charged include several figures from the powerful local Ampatuan clan.
It comes after martial law was declared on Saturday in Maguindanao province, where the killings took place.
Two weeks ago a clan leader and local mayor Andal Ampatuan Jr surrendered to the authorities and was charged with multiple counts of murder.
Police say Mr Ampatuan Jr organised the attack and killed many of the victims himself.
His father, Andal Ampatuan Sr - who was detained at the weekend - was among those charged on Wednesday. The patriarch is a close ally of President Gloria Macapagal Arroyo.
Prosecutors say that after the killings, those charged directed each other "to rise publicly and take arms against the Republic of the Philippines", Reuters news agency reported.
The Ampatuans are reportedly accused of forming "a private army to resist government troops", in the Maguindanao provincial prosecutor's charge sheet.
Members of a rival clan and 30 journalists were among those killed in the 23 November massacre.
The victims were part of a group on their way to file the candidacy of one of their leaders for elections in 2010.
The Philippine national police chief, Jesus Versoza, said the security forces were working hard to find all those responsible for the killings.
"We have so far identified 161 suspects that directly participated in the gruesome massacre of our media friends. The PNP [national police] and the AFP [armed forces] is doing its best to solve this barbaric act, and we will exhaust all our resources so that all the perpetrators will be brought to justice."
Government militiamen and other Ampatuan clan members are among the wanted.