LA MESA, Calif. -- A 34-year-old woman and a 31-year-old man are hospitalized Friday after each was knocked unconscious during a robbery in La Mesa, police said.

The woman was waiting for the man in the 24 Hour Fitness parking lot at 5601 Grossmont Center Drive shortly before 8:30 p.m. Thursday when two robbers approached and demanded her purse, La Mesa police Sgt. Bret Richards said.

She gave up her purse, then was grabbed by her shoulders and pushed up against a tree. Richards said her head struck the tree in the process, causing her to briefly lose consciousness.

Around that time, the male victim showed up to meet the woman and tried to intervene. A third suspect, who was acting as a lookout, struck the man in the back of the head, causing him to lose consciousness, Richards said.

The man came to a short time later and found he was surrounded by all three suspects, who were kicking and punching him in the head and torso, according to Richards.

The robbers then took items from the man at gunpoint before running toward the Grossmont Trolley Station, Richards said.

Both the man and the woman were taken to the hospital. The man had contusions to his torso and complained of head pain, while the woman complained of head, neck and back pain, Richards said.

Police described all three suspects as light skinned Hispanic men, 18-20 years old, between 5 feet 10 and 6 feet tall, with thin builds. They all had shaved heads and were wearing dark pants with white tank tops, Richards said.