WESTMINSTER, Colo. — The weeklong search for a 10-year-old Colorado girl became a murder investigation after authorities identified a body found in a suburban Denver park as that of fifth-grader Jessica Ridgeway.

"Our focus has changed from the search for Jessica to a mission of justice for Jessica," Westminster Police Chief Lee Birk said Friday. "We recognize there is a predator at large in our community."

Anxious parents kept close watch over their children. Fueling the frustration: The FBI again urged residents to report any suspicious activity by people they know.