BALTIMORE (AP) — A Baltimore fire department spokesman says exhaust fumes from generators outside a post office building are being blamed for sickening employees.

Fire department spokesman Kevin Cartwright says two people were taken to hospitals from the main post office complex and a total of 58 were evaluated at the scene, including the two that were transported. He says elevated carbon monoxide levels were detected after firefighters responded to a report of a fall at the building about 8:30 a.m. Monday, and other employees began reporting symptoms. The conditions of the two were not immediately known.

Cartwright says generators outside the building that activated following a power outage a few hours earlier are believed to be responsible.

Post Office spokeswoman Yvette Singh says operations at the main building were not affected.