According to a report posted on Kavkaz Center , Umarov was poisoned on 6 August 2013 .
According to a report posted on Kavkaz Center , Umarov was died at dawn on 7 September 2013 .
According to a report posted on Kavkaz Center , Umarov was poisoned on 6 August 2013 and died at dawn on 7 September 2013 .