Addis Ababa - Witnesses confirm that seven workers died and more than 30 were injured in a gas explosion at Ethiopia's national stadium construction site last month.The explosion was not reported until the Addis Standard published interviews with survivors on Tuesday. The government has been criticised for not disclosing the August 8 blast.Employees of China State Construction Engineering Corporation, which is building the stadium, declined to comment on Wednesday. Government officials could not be reached.One construction worker tells The Associated Press that seven colleagues died and 32 were injured, 10 of them badly. The worker spoke on condition of anonymity for fear of retaliation.Nurse Woinishet Melaku with the nearby government health center says she treated four badly burned victims. She says Chinese managers chased away most responding health and security workers.