Police said the man was acting "suspiciously" and walking around "checking conference room doors" and "going up and down in the elevator near the lobby."
The man was confronted by a chaperone and identified himself as "Sgt. Major Travis Palmer" before saying he had to take a phone call and left the premises.
2 MEN FOUND DEAD NEAR UTAH-ARIZONA BORDER AFTER CANYONS FLOOD
Police in Flagstaff, Arizona, are searching for a man who may have spiked the drinks of JROTC students. (Flagstaff Police Department)
About 20 to 30 minutes after he left, approximately six female students and one male student fell ill and began vomiting while experiencing nausea and dizziness.
The Facebook post says the students "thought their drinks had been spiked."
ARIZONA 19-YEAR-OLD ARRESTED FOR DOUBLE MURDER SEVERAL MONTHS AFTER PARENTS WERE FOUND SHOT TO DEATH
Double Tree Hotel at 1175 W Route 66 in Flagstaff, Arizona. (Google Earth)
Several students were taken to Flagstaff Medical Center for medical treatment.
Flagstaff Police released an image of the man who has a mustache and is wearing a hat and dark-colored jacket.
Police say the man in his 40s or 50s and stands approximately 6 feet tall with a large build.