Harry sprang toward the flame door, but Voldemort screamed "SEIZE HIM!" and the next second, Harry felt Quirrell's hand close on his wrist. At once, a needle-sharp pain seared across Harry's scar; his head felt as though it was about to split in two; he yelled, struggling with all his might, and to his surprise, Quirrell let go of him. The pain in his head lessened -- he looked around wildly to see where Quirrell had gone, and saw him hunched in pain, looking at his fingers -- they were blistering before his eyes. (Harry Potter)
Which one does ‘his’ indicate, Harry or Quirrell?