Hundreds of Bolivian Indians are winding up a weeks-long march against government plans to destroy part of an Amazon nature refuge to build a highway, and now are just one day's walk from La Paz, the group's leaders said Tuesday.

The protesters, who left the northern city of Trinidad in mid-August, were about 30 kilometers (20 miles) from La Paz when they started walking on Tuesday from the town of Pongo to Urujara, about 10 kilometers from the capital.

The marchers, including women, children and elderly people, have endured heavy rains, frigid temperatures, difficult mountainous terrain and police brutality during their 600 kilometer (370-mile) journey.

Earlier this month, President Evo Morales agreed to postpone construction of the roadway, a delay which was later approved by Bolivia's legislature.

But the protesters are seeking assurances that the project -- or at least the Amazon portion of it -- will be scuttled for good.

The Brazil-financed road was to have run through the Isiboro Secure reserve, leveling an ancestral homeland inhabited by some 50,000 native people from three different indigenous groups.

These isolated groups, from the humid lowlands, are not from the main indigenous groups that make up most of Bolivia's population, the highland Andean Aymara and Quechua peoples.

The lowland people fear their traditional lands may be overrun by landless highland farmers.

Work on the highway, which had been due to be operational in 2014, began in June, although not on the segment running through the reserve.