Amrish Puri was suffering from myelodysplastic syndrome, a rare kind of blood cancer, and had undergone some brain invasive surgery for his condition after he was admitted to the Hinduja hospital in 2004.
Amrish Puri died following a brain haemorrhage on 12 January 2005. His condition required frequent removal of the blood accumulated in the cerebral region of the brain.

Amrish Puri had slipped into coma shortly before his death on 12 January, 2005. In a career spanning over three decades, the veteran actor starred in over 200 films.
We miss you Amrish ji!