Police in Chile say two Roman Catholic churches have been burned in a southern region that the Mapuche indigenous group claims as its ancestral territory.

The arson attacks on the wooden structures took place late Wednesday. No one was injured.

The attacks come just days before the start of an investigation into 11 indigenous people arrested for alleged involvement in the arson killings of an elderly couple.

Werner Luchsinger and his wife, Vivian MacKay, died in 2013 defending their property from hooded trespassers. A Mapuche leader has been the only person charged.

Authorities said Thursday they found pamphlets scattered near the burned churches demanding the release of those arrested. Some are signed by the radical Mapuche group "Weichan Auka Mapu" that has claimed about 40 attacks in the area.