OKARA  -   Two suspects were killed while two constables sustained bullet injuries in a shootout that took place in the jurisdiction of A-division police station here.  Police said on Monday that four suspects were fleeing after looting a citizen when on information, a police team chased the outlaws. Seeing police, the bandits opened fire, injuring  two constables- Wasim and Suhail on the spot.  In a retaliatory firing, two robbers who have yet to be identified received critical bullet wounds and died on the spot while their two accomplices managed to escape.  The police seized a motorcycle, a kalashnikov and illegal weapons from the site of encounter. The injured cops have been shifted to hospital for medical treatment.  Police were investigating.