A bag containing 20 live rounds of an SLR belonging to Greyhounds constables went missing in the city on Tuesday. The constables boarded the bus at Visakhapatnam and were proceeding to Ongole. According to sources, the constables kept the magazine containing the bullets in the bag. They realised that the bag was missing after they reached Vijayawada. Following a complaint, the Krishnalanka police registered a case and were investigating.