MINNEAPOLIS (AP) -- Seven agents of the Transportation Security Administration at Minneapolis-St. Paul International Airport were examined at a hospital after reportedly being exposed to fumes at an airport checkpoint.

Officials say no cause of the reported fumes has been discovered.

Metropolitan Airports Commission spokeswoman Amanda Greene Guentzel says there were reports of a smoky odor at about 9:30 a.m. Friday at Checkpoint 2.

She says an investigation by the airport's Fire Department revealed no fire, and there was no visible smoke.

Seven agents were taken by ambulance to Hennepin County Medical Center after feeling ill.

All seven have been released from the hospital.

Two additional officers left work and went home.

The checkpoint has reopened after being closed for over an hour.

Airport operations were not affected.