(ABC NEWS) -- The search for missing Colorado 10-year-old Jessica Ridgeway has taken a turn after officials said the girl's back pack and water bottle were found today.
The Westminster Police Department tweeted a message asking people to stay out of the area while they brought in tracking dogs to follow the lead.
Jessica was last seen on Friday morning when she left to walk three blocks from her Westminster, Colo., home to meet friends for the walk to school. It was a route she took every day, but this time she never got there.
The discovery of the back pack and water bottle came after a day and a half of searching that yielded precious few leads.
On Saturday, an army of eight hundred volunteers scoured trails and hillsides near Jessica's home.
"Right now they're just asking us to find anything that's out of the ordinary, any kind of evidence we could find," said volunteer Monty Yanker.
Amber Alert Issued in Colorado; Search for Jessica Ridgeway Watch Video
Police officers and FBI agents manned road blocks, asking drivers if they had seen or heard anything out of the ordinary. Officers also knocked on doors.
An Amber Alert was issued Friday night for the 10-year-old, nearly eight hours after she disappeared.
When Jessica didn't show up for class, school officials called her home.
But Jessica's mother, who works the overnight shift at a tech company, was asleep. She didn't get the message, which delayed her calling police.
"When we start with an eight-hour delay, or a delay as substantial as this, the distance that she could have wandered even on her own just gets huge," Westminster Police Detective Trevor Materasso said.
Police say that Jessica's father, who lives out of state, is in a custody battle with Jessica's mother. Police do not believe Jessica is with him, but are not ruling anyone out.
"We don't have a person of interest. And we are going to look at every angle multiple times," Materasso said.
Jessica was last seen wearing blue jeans, black boots, a black puffy jacket, and pink and purple glasses, ABC affilate KMGH-TV in Denver reported.
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