A Sonora police officer was seriously injured early Saturday after he lost control of his patrol car and hit a tree in Sonora while chasing a suspect who got away but was arrested later, authorities said. Officer Jeff Aitken, 31, suffered major injuries and was taken by ambulance to Doctors Medical Center in Modesto, according to the California Highway Patrol. Sonora police said Aitken was listed in critical but stable condition Saturday afternoon. Aitken was wearing a seat belt. The incident started about 1:40 a.m. on Morningstar Drive, when the officer spotted Peter Loren Barrett, 20, of Sonora driving a 1994 BMW, said Sonora police Chief Mark Stinson. Aitken suspected Barrett was driving under the influence, so the officer attempted a traffic stop, Stinson said. Barrett fled, so the pursuit started and continued north on Greenley Road and then east on Lyons Bald Mountain Road, the CHP reported. Aitken was traveling about 80 mph when his patrol car entered a curve in the road and he lost control, the CHP said. The patrol car went off the road, struck a tree and came to rest, blocking the road in both directions. Stinson said police found the BMW abandoned a short distance from the crash. About 1 p.m., Barrett called a tow company asking if he could pick up his car, and the tow company notified police. Stinson said officers took Barrett into custody at the tow yard when he arrived to pick up his car. Police arrested Barrett on suspicion of resisting arrest resulting in serious bodily injury and the felony of evading an officer and causing serious bodily injury.