The death toll in the heat wave sweeping across Orissa has risen to three and authorities are investigating 38 more deaths occurred this month to find out if they were due to sunstroke, an official said today.

"Three people died of sunstroke - one each in the districts of Jajpur, Ganjam and Jagatsinghpur. They died on April 24, April 20 and April 1 respectively," said Durgesh Nandini Sahu, officer on special duty in the state revenue control room.