MODESTO, Calif. (AP) -- Police returned to the home of missing pregnant woman Laci Peterson on Tuesday to search for clues in her disappearance and drove away with her husband's new truck.
The search came after police said they made new unspecified findings in the case of the 27-year-old substitute teacher who vanished on Christmas Eve.
"Discoveries during the investigation have necessitated the revisiting of the scene," said Modesto Police Detective Doug Ridenour. He did not elaborate and said the search warrant application was sealed by court order.
Officers removed seven grocery bags of potential evidence from the house and took them to an unmarked police car and a truck marked "crime scene team."
It was the second time officers have used a warrant to gather evidence at the one-story house that features a pool in the back yard.
Laci Peterson's sister, Amy Rocha, spent a couple of hours inside the house with police, but it was not immediately clear what role she may have played in the search.
Officers used a warrant Dec. 26 to seize Scott Peterson's truck and 14-foot boat and trailer after he reported his wife missing when he returned from a solo fishing trip in San Francisco Bay.
With those vehicles still in police custody, Peterson traded in his wife's Land Rover for a new pickup truck recently. On Tuesday, investigators took the new truck away from the house to search for evidence, said Sgt. Ron Cloward.
Ridenour downplayed the significance of the day's events, saying it was routine to return to the house where the couple lived and he said it was "not a big part of our focus." He said Peterson would be able to get his truck back and return to his house at the end of the day.
Peterson, 30, was home when the search began Tuesday and was cooperative with police, Cloward said. A few hours after the search began, Peterson left with his bags packed and drove off in another vehicle. He returned a few hours later and handed some papers to police before leaving.
It was not immediately clear what he gave police or where he went.
Police have not named Peterson as a suspect in his wife's disappearance but they said they have not ruled him out.