Brazilian police arrested two brothers Sunday in the killing of two Amazon rainforest activists in May. A third suspect remains at large.

Brazilian authorities say the suspects were found hiding in a rural area of Para state. The region is known for violence related to land disputes.

The rainforest activists had been vocal about illegal logging and ranching in the Para state region.

Catholic Land Pastoral says they have found instances of more than 1,150 activist murders in the last 20-years.

The French news agency reports that six farmers or activists were murdered between May and June of this year for their efforts to defend the rainforest.