(Undated) -- Sentencing for the man convicted of killing University of Iowa student Mollie Tibbetts is being delayed.
Christhian Rivera was originally scheduled to be sentenced on Thursday.
The judge overseeing the sentencing granted the delay as Rivera's lawyers say they need more time to prepare a motion for a new trial.
The lawyers say they have information that another person has confessed to killing Tibbetts--that she was kidnapped as part of a sex trafficking ring.
During his trial in May, Rivera said two other men were responsible for killing Tibbetts, and left him to hide her body in the corn field where she was eventually found.
Rivera was convicted of first-degree murder, which carries a mandatory life prison sentence under Iowa law.