BATON ROUGE, La. (AP) — Louisiana won't carry out its next scheduled execution before January 2018 if a federal judge approves a request by state Attorney General Jeff Landry's office.

In a court filing Tuesday, Landry's office asked for an 18-month extension to a judge's order that delayed the execution of Christopher Sepulvado.

A federal lawsuit challenging Louisiana's method of lethal injection has kept Sepulvado's execution on hold since February 2014. The state's execution protocols changed as drugs used in lethal injections became scarce.

U.S. District Judge James Brady previously ruled out executing Sepulvado and at least four other death-row inmates before July 11, 2016. Landry's office says it would be "prudent" to extend the order until Jan. 8, 2018, given the litigation's "fluid state."

Sepulvado was convicted of murdering his 6-year-old stepson in 1992.

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