Authorities say whatever made more than a dozen Oklahoma City workers sick remains a mystery after testing detected nothing unusual at a downtown office building.
Oklahoma City Battalion Fire Chief Benny Fulkerson said the investigation into reports of dizziness, headaches and difficulty breathing has closed with no cause for the illnesses. Fulkerson said air monitors did not detect natural gas or carbon monoxide and no odors indicated a sewage leak.
About 300 employees in Oklahoma City's finance and information technology departments were ordered out of the building Thursday after several reported feeling sick. Fulkerson said 19 were treated at the scene.
City spokeswoman Kristy Yager said three employees were taken to a hospital and were treated and released. Officials declined to say why the three were taken to a hospital.