QUETTA - Two traffic police constables were killed and three passers-by sustained injuries when unidentified armed persons opened indiscriminate fire at them on Prince Road here on Tuesday night. Constable Sher Muhammad and Younas were performing their duties on Prince Road when unknown armed assailants riding a motorbike opened indiscriminate fire at them and managed to escape from the scene under the cover of darkness. As a result, both policemen including three other passers-by received bullet wounds. The injured were rushed to the Civil Hospital Quetta, where police constables succumbed to injuries. The other injured were identified as Shakeel Ahmad, Naseer Ahmad and Rehan. The relatives of deceased and other policemen got infuriated and chanted slogans against the government for its failure and also smashed windowpanes of hospital. Police and other law enforcement agencies beefed up security in Quetta, however, no arrest was reported till filling this report. Meanwhile, unknown armed assailants killed two people including a woman in Nasirabad district on Tuesday. According to reports reaching here, unknown armed assailants entered into a house in teshil Tambo of Nasirabad and opened indiscriminate firing on Manzoor Ahmad and his sister-in-law. Resultantly, both died at the spot. The assailants escaped from the scene after committing crime.  The cause of attack was stated to be old tribal dispute. Police have registered a case and started investigation.