A maximum-security prison guard who delivered frozen meat with tools hidden inside to two inmates before they escaped will be arraigned on charges of promoting prison contraband and other offenses.

But a lawyer for correction officer Gene Palmer says his client had no knowledge any contraband was inside the meat.

"He did pass the hamburger meat. He shouldn't have done it. He apologized for it," said defense lawyer Andrew Brockway Wednesday night. He insisted Palmer didn't know the inmates were trying to escape.

Palmer worked at the Clinton County Correctional Facility in upstate Dannemora, where inmates David Sweat and Richard Matt were reported missing on June 6.

He was being held on $25,000 bail Wednesday night after he appeared before a judge in Plattsburgh to face charges of promoting prison contraband, tampering with physical evidence and official misconduct.

Palmer will plead not guilty at his arraignment on Thursday, Brockway said.

Authorities say the inmates cut through the steel wall at the back of their cells, crawled down a catwalk, broke through a brick wall, cut their way into and out of a steam pipe and then sliced through the chain and lock on a manhole cover outside the prison.

Sweat, 35, was serving a life sentence without parole in the killing of a sheriff's deputy. Matt, 48, was doing 25 years to life in the kidnapping, torture and hacksaw dismemberment of his former boss.

Prison employee Joyce Mitchell also has been charged with helping them escape. Mitchell, a prison tailor shop instructor, has pleaded not guilty and remains in custody.

Clinton County District Attorney Andrew Wylie said Mitchell told investigators she smuggled hacksaw blades, a screwdriver and other tools into the prison by placing them in the frozen hamburger meat. He said she then placed the meat in a refrigerator in the tailor shop and Palmer took the meat to Sweat and Matt, who were housed in a section where inmates are allowed to cook their own meals. The district attorney said the guard didn't know the tools were inside the meat.

Brockway said Palmer continues to cooperate with investigators who are trying to track down the fugitives.

"He understands this is a public emergency, and any information that he has he will give to authorities to help capture Mr. Sweat and Mr. Matt," Brockway said.

Palmer had been placed on leave on Tuesday. At the time, his attorney told television station WPTZ he was completely forthcoming during several hours of questioning on Saturday.

"I can 100 percent confirm that he did not know they were planning on breaking out of the prison," Brockway said.

Searchers hunting for the escaped killers Wednesday contended with steep slopes, thick woods, sticky bogs, biting bugs and the possibility that the pair on the lam from prison for 19 days is armed.

Police said they remain almost fully certain that Sweat and Matt spent time recently at a hunting camp about 20 miles west of the correctional facility near Owls Head. A hunter said he saw a figure bolting from the cabin on Saturday morning. But after days of intense searching with dogs and helicopters, police still had no substantiated sightings of Sweat and Matt.

State police Maj. Charles Guess said Wednesday authorities don't have confirmed evidence a shotgun was stolen from the hunting cabin near Owls Head but they've always assumed the escapees were armed. Weapons and ammunition are typically stored in camps, but not everyone keeps an inventory, he said.