A hotel in Ann Arbor, Michigan, was evacuated Saturday night because carbon monoxide levels were dangerously high. 

The Ann Arbor Fire Department reported its crews responded to a call of a gas odor about 11:10 p.m. at the EVEN Hotel Ann Arbor South, 600 Briarwood Circle. The hotel has 107 rooms and is near Briarwood Mall, providing shuttle service to University of Michigan's stadium on football game days, according to its website. 

U-M hosted Central Michigan in Ann Arbor for an afternoon game that day. Friday through Sunday was also Parent & Family Weekend at the U-M campus. 

When firefighters arrived, they found carbon monoxide levels in the basement were approaching 200 parts per million.. 

"These levels of carbon monoxide could have been fatal," the fire department said. 

The hotel was evacuated until carbon monoxide levels were back to safe readings, and DTE Energy crews also responded to the scene. The ventilation efforts lasted several hours. 

Firefighters said the cause was a bank of four malfunctioning water heaters. Gas service was shut off for the equipment.  

No injuries were reported from the incident.