It was the closing stages of the match, a soccer derby in Indonesia's East Java province, and 29-year-old spectator Ahmad Nizar Habibi said he had a gut feeling things were about to turn ugly.

"I wanted to leave, but suddenly I heard explosions," he said, describing rounds of tear gas fired as Saturday's nighttime match ended and fans invaded the field, angered by the home team's loss.

"We couldn't see. Fans were screaming and we couldn't breathe," said Habibi.