Elizabeth Collins, Lyric Cook-Morrissey: Authorities "grasping for straws" in missing Iowa girls case, sheriff deputy says

(CBS/AP) DES MOINES, Iowa - Authorities say they've uncovered no significant evidence in the search for missing cousins Elizabeth Collins and Lyric Cook-Morrissey, three days after their bicycles were found near a lake in northeast Iowa.

PICTURES: Hundreds search for missing Iowa cousins

Black Hawk County Sheriff's Deputy Rick Abben says local, state and federal authorities have been "grasping for straws" in the frantic search for 8-year-old Elizabeth and her 10-year-old cousin, Lyric.

Abben says no eyewitnesses have reported seeing the girls. They've been missing since leaving their grandmother's house Friday afternoon in Evansdale.

Several hundred volunteers helped search the area Saturday and Sunday around Meyers Lake in Evansdale.

Abben says authorities have been doing house-to-house searches around the clock. He says it's still considered a missing persons case.

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