SAO PAULO, July 7 (Reuters) - Residents in Brazil's Amazon region blocked on Friday a key way for the transport of Brazilian grains to northern ports in a protest over increased protections for the rainforest, grains industry groups said on Friday.
Farmers, ranchers and residents in the Amazonian state of Para blocked the rugged BR-163 jungle road near the town of Novo Progresso.
"The BR-163 road is completely blocked. There is already a large line of trucks backed up there," Vanderlei Ataídes, head of the Para State's association of soy and corn producers, said by telephone.
The road is used to transport soy and corn from center-west Brazil to northern exporting ports. Top grains producer Mato Grosso State is at the peak of winter corn harvesting.
Abiove, a Brazilian association representing commodities merchants and processors, said on Friday the blockage reduced the amount of grains flowing to northern ports to 25 percent of the normal volume.
The protest turned violent late Thursday when a group set fire to semi-truck carrying eight new pickups to be used by government environmental agents to patrol the forest. Police were investigating the incident.
The protesters are angered over a recent veto by President Michel Temer of a congressional bill that would have reduced the size of the Jamanxim National Forest. That bill would have opened up more land to farmers and ranchers.
Temer's veto bill last month followed protests from environmental organizations who opposed the bill that would have reduced the protected reserve by over 480,000 hectares (1.18 million acres). (Reporting by José Roberto Gomes; Editing by Cynthia Osterman)