Bangladesh's top-ranked chess grandmaster Ziaur Rahman died Friday at the age of 50 after suffering a stroke and collapsing on his board in the middle of a national championship match, an official said. Bangladesh Chess Federation general secretary Shahab Uddin Shamim told AFP that Ziaur collapsed during his 12th round match of the championship against fellow grandmaster Enamul Hossain before he was declared dead at a hospital in the capital Dhaka. "Players and officials present in the hall room took him to the hospital quickly after he collapsed. Upon reaching there, doctors said he had already died," Shamim said.