LINCOLN, Neb. (AP) — An official says Nevada doesn't plan to return one of the drugs obtained for use in an upcoming execution, despite a demand by pharmaceutical company Pfizer that its drugs not be used for lethal injections.

A spokeswoman acknowledged the Nevada Department of Corrections received a letter Oct. 4 similar to one received by officials in Nebraska and reported by the Omaha World-Herald.

The Nevada letter, obtained by The Associated Press, seeks the return of the sedative diazepam or the opioid painkiller fentanyl if it was manufactured by Pfizer.

Nevada prisons spokeswoman Brooke Keast says the state is under no obligation to return Pfizer-made diazepam that the state obtained last May through its normal pharmacy supplier, Cardinal Health.

Pfizer in May 2015 said it would block distribution of its drugs for executions in the 31 states in the U.S. with the death penalty.