Guam Fire Department units responded to Route 3 and Fern Terrace in NCS, Dededo just before 5 p.m. for a reported an overturned vehicle.
According to GFD, the crash involved two vehicles with one overturning in the collision.
GFD said the overturned vehicle had "a total of two occupants, one patient with serious injuries."
GFD confirmed the patient seriously injured is male individual in his 40's. The man was transported to Guam Regional Medical City.
The Guam Police Department has yet to issue a statement regarding the incident.