(CBS/WISH/AP) BLOOMINGTON, Ind. - The week long search efforts for missing Indian University student Lauren Spierer were expanded to southern Indiana lakes Wednesday and Thursday.
A dive team searched Lake Monroe using boats and sonar for signs of the missing girl but has so far found nothing. The search was reportedly sparked by an anonymous tip, police say.
Over 100 volunteers reportedly searched the 100-acre Griffy Reservoir for clues, but also failed to turn up any information pertaining to Spierer's disappearance.
"We're still needing to pretty much look everywhere," Bloomington police Lt. Bill Parker said at a news conference Thursday morning.
Spierer's father, Robert Spierer, asked that property owners around Bloomington check wooded areas, barns and sheds on their property for any signs of his daughter.
Lauren Spierer was last seen walking alone toward her Bloomington apartment building around 4:30 a.m. last Friday.
Spierer's family is now offering a $100,000 reward for any information leading to the student's safe return, according to CBS affiliate WISH-TV. An additional $45,000 is reportedly being offered by various donors.