Bolivian President Evo Morales has suspended construction of a controversial highway through a rainforest as more government officials resign following a police crackdown on protesters opposed to the project.

Officials say the deputy interior minister, Marcos Farfan, resigned Tuesday and could be a subject in an investigation into the police action. Immigration director Maria Rene Quiroga also stepped down, criticizing the crackdown as “unforgivable.”

Defense Minister Cecilia Chacon announced her resignation Monday. Chacon said she did not agree with the government's decision to disperse hundreds of demonstrators who have been marching toward La Paz from the city of Trinidad since August to show their opposition to the highway.

President Morales was also critical of the police action against the demonstrators and promised an investigation. On Sunday, riot police fired tear gas at marchers gathered in the Yucumo area. Police rounded up several protesters, who were later released after area residents blocked an airport landing strip to prevent authorities from flying the detainees out of the area.

The demonstrators say the $415 million project threatens a protected area of rainforest and that their right to be consulted with violated.

The nature preserve is home to Amazon Indian groups, who have lived in isolation for years. The local people fear outsiders will try to develop the region.

President Morales had angered indigenous people by saying the road would be built through the Isiboro-Secure Indigenous Territory National Park “whether they like it or not.” Activists have said they will be ready with bows and arrows when the time comes to protect their land.

Mr. Morales is Bolivia's first indigenous president. In past speeches, he has said all nations must respect “Mother Earth” in their environmental policies.