Indian writer and social activist Mahasweta Devi, who used her writing to give voice to the oppressed poor tribal and forest dwellers, has died aged 90.

Devi, who wrote mostly in the Bengali language, had been in a hospital in the eastern Indian city of Kolkata where she was being treated for a kidney ailment for the past two months.

Her major works dealt with the suffering of poor labourers and forest dwellers who had lost their lands due to industrial and urban growth.

She founded several social organisations to help fight for the rights of indigenous people.

Devi was the recipient of several awards including several of India's highest civilian and literary awards.

In 1997 she was awarded the Ramon Magsaysay award, a Philippine honour considered to be the Asian Nobel Prize.

Her citation for the Magsaysay award recognized her "compassionate crusade through art and activism to claim for tribal peoples a just and honourable place in India's national life."