Police officers in one major U.S. city are fighting back against Waze, a popular mobile app that reveals their locations to motorists.Hundreds of officers in the Miami area have downloaded the app, which lets users provide real-time traffic information and identify areas where police are conducting speed enforcement. The local NBC affiliate says the officers are flooding Waze with false information on their activity in an attempt to make the app's information less useful to drivers.Disclosing the location of police officers "puts us at risk, puts the public at risk, because it's going to cause more deadly encounters between law enforcement and suspects," Sgt. Javier Ortiz, president of the Miami Fraternal Order of Police, tells the news outlet Some police officers believe the precise information could be used by criminals to carry out heinous attacks, like the one in December in which a man ambushed New York Police Department officers Wenjian Liu and Rafael Ramos, shooting them to death The National Sheriffs' Association first raised concerns about the Waze app, which is used by millions of motorists. Not all police officers agree that it poses a threat, however. If a criminal wants to hurt an officer, they say, they don't need an app to find a target. And high-visibility enforcement may ultimately reduce crime.A spokesperson for Waze, which is owned by Google, said the app could actually help improve traffic safety because it encourages speeding motorists to slow down."Most users tend to drive more carefully when they believe law enforcement is nearby," spokesperson Julie Mossler told The Associated Press.Since law enforcement raised concerns about the app, it has actually gained popularity. The AP says it is the eighth most-popular free app on Apple's rankings.