Scott Peterson's defense team says they have found the mystery woman who can provide information about the real killers of the California murder suspect's 8-months-pregnant wife, Laci, and their unborn child.

The sources told Fox News they're working to transport the woman to a safe location because they fear retaliation against her if her identity is revealed.

Peterson’s lawyers have been talking for weeks about evidence they say will prove someone else kidnapped and murdered Laci.

Now, the defense team says they are only days – if not hours – from locating the people who they believe are responsible for the killing.

"We would not go out on such a limb if we weren't confident we could deliver,” a defense source told Fox News. “We believe in a matter of days, the real killer may be found and police investigators will have egg on their face."

Laci, 27, disappeared from her Modesto, Calif., home on the day before Christmas. Her husband Scott told police that he was on a fishing trip in Berkeley Marina, in San Francisco Bay, and returned to find his pregnant wife gone.

Last month, Laci's body and that of the couple’s nearly full-term son, Conner, washed up on shore in the same area Scott said he’d been fishing.

Even before the bodies were positively identified, police arrested Scott and charged him with two counts of first-degree murder. When he was apprehended in southern California, close to the Mexican border, Scott had dyed his hair blond and was carrying a large sum of cash and his brother's passport.

Still, Peterson's lawyers contend that the real killers are still out there. They say the murderers are linked to a Satanic cult in Central Valley, Calif., and to a suspicious brown van that was spotted near the Petersons’ home on the day Laci disappeared. Sources say one of the people in the van, which was carrying men and women, had a "666" devil-worshipping tattoo.

The sources say they have had trouble locating the people in the van, because when the cult members were interviewed by police a few weeks after Laci's disappearance, they provided no known home address.

Authorities quickly discounted the van as having any ties to Laci's disappearance, saying the vehicle belonged to landscapers. But there was no landscaping equipment found inside, according to defense sources.

The sources told Fox News that they have seven investigators currently searching for the van. They say that when it’s found, they’ll have legal jurisdiction to seize the vehicle.

"We could solve this case in a matter of days, if not sooner," the sources said.

In addition to the mystery woman, the defense team sources say they have hard evidence to back up her claims. They say that all the information together proves someone other than Scott committed the crime.

Police were apparently told about this woman early in the investigation, the sources say, but authorities never interviewed her because they believed the Satanic cult theory was "bogus."

A prosecution source told Fox News that investigators still believe the Satanic cult theory is "absurd and laughable," but the defense says that — as crazy as it might sound — they have the facts to back it up.

The defense sources also say police were too quick to discount the theory that Laci's case may be tied to that of 24-year-old Evelyn Hernandez, a pregnant woman whose torso was found in San Francisco Bay in July 2002. Hernandez vanished May 1, 2002.

In the Satanic calendar, the period of April 26-May 1 is called a "grand climax.”  Another important day in that calendar is Dec. 24, called a "high grand climax day." Laci disappeared Dec. 24.

Additionally, defense team sources told Fox News that they have four specific witnesses who say they saw Laci walking her dog on Dec. 24.

Prosecution investigators say they have also talked to those four witnesses, but they believe the witnesses probably saw someone else who looked like Laci.

Police sources maintain they have a strong case against Scott Peterson, including evidence that shows the crime occurred in Peterson's home Dec. 23.

Fox News' Catherine Donaldson-Evans contributed to this report.