Officers found the body of a woman still burning just after 10 p.m. on Skyline Boulevard near the gate of Redwood Regional Park. That's near Oakland's Montclair neighborhood.
One resident believes the park's location may have played a part in the crime.
"I definitely think it's because this area is remote," resident Ed Gerber said. "And probably the people that were disposing of the body were looking for some place that nobody's going to pay attention while they were doing it, which they might elsewhere in the area."
Because of the condition of the burned body, the identity of the victim may not be known for months.
The Alameda County Coroner's Office has not yet released a cause of death.
The Skyline Boulevard entrance to Redwood Regional Park was open to the public Sunday as officers continue to investigate the incident.