Backers of Zapatista rebels march by the thousands in southern Mexico

Masked Mayan Indians who are members of the Zapatista National Liberation Army (EZLN) march in line to the mayor's office in San Cristobal de las Casas, Chiapas state, Mexico, Friday, Dec. 21, 2012. On Friday, Zapatistas in several cities are marching to the city mayor's office for a gathering where they will listen to a message from their leaders. (AP Photo/Ivan Castaneira) (The Associated Press)

Masked Mayan Indians, members of the Zapatista National Liberation Army (EZLN), march in line to the mayor's office in San Cristobal de las Casas, Chiapas state, Mexico, Friday, Dec. 21, 2012. On Friday, Zapatistas in several cities are marching to the city mayor's office for a gathering where they will listen to a message from their leaders. (AP Photo/Ivan Castaneira) (The Associated Press)

Thousands of supporters of the leftist, indigenous Zapatista movement have marched in the southern Mexican state of Chiapas to commemorate a 1997 mass killing and the end of the current cycle of the Mayan calendar.

Organizers said some 12,000 people marched in the cities of Ocosingo, Palenque and San Cristobal de las Casas. The marches marked the Dec. 22 killing of 22 indigenous Zapatista backers by a rival armed local group. They also marked the conclusion of a 5,125-year cycle in the Mayan calendar.

The Zapatistas last marched in May 2011 in support of a movement against drug-cartel violence in Mexico.