Assailants in the southern Philippines 23 November 2009 killed a group of Muslim women from the politically prominent Mangudadatu family, including the Vice Mayor of Mangudadatu municipality and the wife of the Vice Mayor of Buluan municipality, their staff members, and accompanying journalists en route to register one of the clan's leading members for a provincial gubernatorial election. Eyewitnesses blamed the massacre on the Ampatuan clan. Rival Ampatuan clan patriarch and former Maguindanao Governor Andal Ampatuan, Sr., and another son, former Governor of the Autonomous Region in Muslim Mindanao (ARMM) Zaldy Ampatuan, were detained in Mindanao on charges of rebellion, which stemmed from their acquisition of a significant arsenal and efforts to block the massacre investigation. Zaldy Ampatuan played a constructive role in coordinating the acts of local militia groups aligned against the Moro Islamic Liberation Front. Both the Ampatuans and the Mangudadatus are affiliated with the Lakas-Kampi-CMD ruling party, and they have at times cooperated in political matters. Both maintain well-armed militias.