This combo made from undated photos provided by the FBI shows cousins Lyric Cook, 10, right, and Elizabeth Collins, 8, who have been missing since Friday, July 13, 2012. (AP Photo/FBI)

Two Iowa girls have been missing for a month, but the FBI says leads make investigators believe the girls are still alive.

Ten-year-old Lyric Cook and her cousin Elizabeth Collins, who has since turned 9, were reported missing July 13 from the Waterloo suburb of Evansdale. The bikes were found at a nearby lake about four hours after their grandmother had last seen them.

The Des Moines Register says FBI spokeswoman Sandy Breault would not discuss the leads nor say whether investigators believe the girls were kidnapped for ransom, abducted by a relative or abducted by a nonrelative.

The likelihood of finding abducted children alive drops as time goes on, but Breault and others say it’s important for relatives and investigators to not give up hope.

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