Thursday, July 13, 2017. It's a somber anniversary date, marking five years since two cousins disappeared while riding their bicycles in Evansdale.

During the investigation, authorities concluded that someone abducted Elizabeth Collins, 8, and Lyric Cook-Morrissey, 10, on July 12, 2012. Five months later, hunters discovered the girls' bodies in a secluded area at Seven Bridges Wildlife Area in rural Bremer County. What happened to the cousins and who is responsible for their deaths remains a mystery.

In the five years since their disappearance, authorities have received multiple tips. They've interviewed more than 1,000 people and investigated more than 300 sex offenders, but still haven't made any arrests in the case. Investigators remain hopeful, though, that someday they'll be able to solve the crime and bring whoever is responsible to justice.

"There is a person or persons out there that can start to lead the families towards the truth of what happened to Lyric and Elizabeth," officials with Cedar Valley Crime Stoppers wrote in a Facebook post recognizing the anniversary. "To the person or persons out there, please reach out and provide that one detail that investigators need in this case. Please let the fifth year be the year this case is closed."

Cedar Valley Crime Stoppers is offering a $20,500 reward for anyone who provides information that simply leads to an arrest in the case. Another $150,000 reward, money raised through private donations and the FBI, is also available for information that results in an arrest and conviction.

Anyone with information is encouraged to contact the Evansdale Police Department at 319-232-6682 or Cedar Valley Crime Stoppers at 855-300-TIPS (8477). Tips may also be left at WWW.CVCRIMESTOP.COM or by texting the word CEDAR, plus the information to CRIMES (274637).

On Saturday (July 15), an awareness event is being held in Evansdale to officially mark the anniversary of the girls' disappearance. A motorcycle ride -- the fifth annual "Memorial Ride and Drive" -- will start and end at Lofty's Lounge on Lafayette Road.