Surat: Thousands of tribals from Dang district participated in a massive rally organised by Akhil Bharatiya Adivasi Ekta Ane Vikas Parishad (ABAEVP) at Ahwa on Monday to protest against long pending issues pertaining to rights of tribal people and proposed construction of dams on Purna, Khapri and Ambika rivers under the river linking project of Gujarat and Maharashtra governments.