A 19-year-old woman reported being robbed at gunpoint in the area of Carter Way around 3 a.m. Monday, Atwater police said Tuesday.
The victim told police three unknown male assailants with a black semi-automatic handgun robbed her of a large amount of cash.
The victim provided few additional details about the robbers.
Police are asking anyone with information about the robbery to call (209) 357-6396 or the department's automated tipline at (209) 357-6390. Tips are kept confidential and callers can remain anonymous.