Tempe police have shifted their search for a missing 19-year-old college student to Tempe Town Lake.
Officers said Adrienne Salinas was last heard from at about 4:30 a.m. Saturday when she called a friend to say she was coming over.
She never arrived.
Salinas' father found her car on Sunday near Brown and Roosevelt streets - about two blocks from her apartment on Ash Avenue.
Salinas' family told CBS 5 News they knew something was very wrong when she never called her dad Sunday to wish him a happy Father's Day.
Authorities Monday night were using robots with sonar to search the lake bottom. The only reason they are searching the lake is to rule out the possibility that she might be in there, officers said.
The lake search was scheduled to continue until midnight.
If you have any information on Salinas' whereabouts, call Tempe police.
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