Tucson police investigated four bomb threats Thursday.
Locations included 5206 S. Nogales Highway, 727 E. Evans, 1183 W. Irvington and 4550 E. Broadway.
Police did not find a bomb at any of the scenes. All locations were evacuated while the police performed sweeps.
The threats are the latest in a string of bomb threats that have been going on all week. There have been at least eight this week.