PHOENIX - Rescues crews are searching for one person who remains "unaccounted for" after a drill rig fell over near Sky Harbor Monday morning.
Phoenix fire said the condition of the person is not known at this point and it's going to take "considerable time" before its determined that the search is either a rescue or recovery effort.
According to fire officials, the drill rig was being used for construction on the Sky Tain guideway system.
Phoenix fire said airport operations were not affected by the incident.
The fire department originally said the drill rig was a crane.
