OKLAHOMA CITY — Oklahoma's prison system chief says the state has the drugs it needs to execute four inmates early next year and plans to administer the same three drugs used in a botched execution this spring, but with an increased dose.

Department of Corrections Director Robert Patton told a federal judge Friday the agency plans to use the exact formula used successfully in 11 executions in Florida, one that he believes is "humane."

The judge plans to rule Monday in a case in which lawyers for 21 death row inmates say one of the three drugs, the sedative midazolam, presents a risk of cruel and unusual punishment.

The drugs were used during the April execution of Clayton Lockett, who writhed and moaned on the gurney before a problem was discovered with an intravenous line.