Police received a call at 8:09 a.m. from someone in the 2300 block of Courtland Ave who heard a woman screaming, Oakland police Officer Holly Joshi said.
Officers responded and found the woman, who said she had been sexually assaulted, Joshi said. The victim was taken to a hospital. Her injuries were not life-threatening, she said.
Investigators believe the attack was not random because the woman had apparently arranged a meeting at that location and may have been set up to be sexually assaulted, according to Joshi.
Police are looking for at least one suspect and are hoping to track down witnesses.
Anyone with information about the crime is asked to call the Police Department's youth and family services division at (510) 238-3641 or the sexual assault tip line at (510) 637-0298.