Saturday marks one year since cousins Elizabeth Collins and Lyric Cook-Morrissey vanished while riding their bicycles in the northeast Iowa town of Evansdale. Twelve months later, the case remains unsolved and the circumstances surrounding their abduction and murders remains a mystery.

Authorities who’ve spent the past 52 weeks reviewing evidence and pursuing leads in the case still have no new information to release publicly. While the lack of information has frustrated both the community and the victims’ families, the chief deputy with the Black Hawk County sheriff’s department says what is known about the case must remain confidential in the interest of justice and to preserve the integrity of the investigation.

Captain Rick Abben made the comments in a press release issued to the media on Thursday. In the press release, Abben said the case is very complex and remains active, with authorities from state, local, and federal agencies continuing to pursue leads and follow-up on information as it’s discovered.

Collins was 8 years old and Cook-Morrissey was 10 when the cousins didn’t come home from a midday bicycle ride on July 13, 2012. Their bodies were found December 5, 2012 in rural Bremer County.

On Saturday, several events are being held in Evansdale to celebrate the girls’ lives and mark the one-year date of their disappearance. Among them are a “Memorial Ride and Drive” fund-raiser and a free meal for anyone who helped in the search for the missing girls last summer.

(Reporting by Elwin Huffman, KOEL, Oelwein)