A dozen inmates from Alabama used a salty snack to trick a new prison employee at the Walker County Jail into opening an outside door last weekend, Walker County Sheriff James Underwood said Monday.

Speaking at a news conference, Underwood explained that a fresh employee unknowingly opened an alternate door while keeping count of inmates in the prison's control room.

The 12 inmates reportedly used peanut butter extracted from their sandwiches to change the door numbers and then when asked to open a wrongly labeled door, the new employee, "hit that lock and out the door they (inmates) went," the sheriff said.

"He should have been more cautious about it," Underwood said, admitting that the employee "made a mistake."

Underwood also detailed the escape, saying that the inmates used blankets to climb over the razor wire fence of the prison located about 40 miles northwest of Birmingham.

No injuries have been reported by citizens or employees after the jailbreak; however, two of the escapees were hurt while fleeing.

One inmate is still at large, while the other 11 have since been caught, Underwood added.

"This is one time we slipped up. I'm never going to make any excuses -- it was a human error that caused this to happen," the Walker County sheriff said, adding that some security deficiencies worth about $300,000 required refurbishing.

Underwood also said inmates at the Walker County Jail would still be served peanut butter sandwiches.