LAS VEGAS (AP) — A federal judge said Thursday he may order Nevada prison officials to disclose the type of drugs they would use for the first lethal injection of a condemned prisoner in the state in 15 years, even if they haven't finalized a plan for how the execution would be carried out.

U.S. District Judge Richard Boulware II also said he might order the district attorney in Las Vegas to join attorneys for the state, convicted mass murderer Zane Michael Floyd and the local newspaper in hearings Boulware is holding on a request to block Floyd’s execution, possibly in late July.

The judge appeared frustrated that Floyd’s attorneys were asking him, in his words, “to stay an execution that hasn’t been scheduled yet,” and that the state has not disclosed the type of drugs it would use, whether it has them, the names of the manufacturers or the lethal injection method to be used.

Randall Gilmer, the state attorney representing the Nevada Department of Corrections and prisons chief Charles Daniels, said the state isn’t obligated to make public its execution plan, called a protocol, until officials complete their confidential “deliberative process" and an execution warrant is issued.

Only then can defense attorneys and the public challenge the plan, Gilmer said.

The deputy state attorney general also expressed concern that once the information is public, officials involved in the execution will face harassment from death penalty opponents.

Boulware is reviewing a log the state is providing to Floyd’s attorneys of documents relevant to the case, to determine which ones should remain sealed.

He denied a bid by an attorney for the Las Vegas Review-Journal to make the log public as part of the court record.

“I fully anticipate that when the protocol is finalized, we will have a significant discovery hearing about a great many things,” Boulware acknowledged.

“It seems to me that the longer this takes — for this execution protocol to be finalized — the longer will be the stay that I ultimately enter as it relates to the execution date,” he said. He said he might consider a block of up to 120 days.

“Mr. Floyd’s entitled to be able to determine whether or not there’s a proper choice made about the drugs or even ... the protocol,” the judge said.

Floyd, 45, is fighting his death sentence for the 1999 shotgun killings of four people and the wounding of a fifth at a Las Vegas supermarket. He lost appeals in state and federal courts, and the U.S. Supreme Court declined to take his case.

A state judge in Las Vegas plans a June 4 hearing — also about the status of the execution protocol — and might issue a warrant for execution for the late July date, Floyd's defense attorney, David Anthony, told Boulware.

The federal judge scheduled his next hearing June 3.

“Between now and then I will consider the extent to which I am going to order the disclosure, or not, of the drugs under consideration,” Boulware said, along with arguments about blocking the execution date.