California The crime scene, alongside a busy freeway off-ramp, was shielded from view by dense brush and tangled tree limbs.
The victims - five people shot to death over the weekend at a spot inhabited by the homeless - were known largely by their nicknames or just their first names.
And Southern California's first significant rain of the season may have washed away evidence.
Police in Long Beach are confronted with a baffling murder mystery.
Three men and two women were found slain Sunday in the seedy neighborhood of warehouses and apartment buildings near the intersection of two freeways. Some of the victims had been shot more than once.
Police said Monday that they had no eyewitnesses and no suspects and had yet to establish a motive for the slayings. But neighbors said people would often drop by to do drugs in the shadows underneath the freeway.