Amid growing controversy over lethal injection protocols, the state of Ohio has postponed the executions of all seven death-row inmates set to die in 2015.

In a statement issued late Friday, the Ohio Department of Rehabilitation and Correction (DRC) says the decision was made in order to afford the state enough time to comply with a new execution protocol and obtain a fresh supply of execution drugs.

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Earlier this month, the DRC halted the combined use of midazolam (a sedative) and hydromorphone (a painkiller) for lethal injections after the January 2014 execution of Dennis McGuire lasted for approximately 25 minutes, during which witnesses saw him gasping for air. And in May, a federal judge ordered Ohio to postpone all executions in order to afford attorneys for death-row inmates time to prepare challenges to the state’s new procedures.

The U.S. Supreme Court on Wednesday granted a stay of execution for three Oklahoma death row inmates until the justices rule on a separate challenge involving the midazolam – a drug that has come under increased scrutiny since three problematic executions, including McGuire’s.

Within the last few years, some pharmaceutical companies have stopped carrying lethal injection drugs over ethical concerns, contributing to a nationwide shortage. In an apparent effort to circumvent the problem, Ohio passed a law in December providing confidentiality to pharmacies that prepare lethal compounds. Since then, four condemned inmates filed a federal lawsuit saying the new law violates their right to due process.

One of just 40 countries in the world that still employs capital punishment, the U.S. in 2014 saw the lowest number of executions in two decades.