HOUSTON (AP) – Attorneys for two Texas death row inmates say state officials have been buying lethal-injection drugs using a long-closed prison hospital’s federal registration number.

The lawyers represent inmates Cleve Foster and Humberto Leal. Foster is set to die next week and Leal in July.

In letters sent Wednesday to the U.S. attorney general and Texas public safety director, attorneys Maurie Levin and Sandra Babcock allege the Texas Department of Criminal Justice has violated federal law for more than 25 years.

They’ve asked for an investigation into whether a federal Drug Enforcement Agency number for the Huntsville Unit Hospital has been used to acquire drugs for executions. They say the hospital closed in 1983.

Department of Criminal Justice spokesman Jason Clark says agency officials are confident they have not violated the law.

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