Three inmates who have violent crime charges escaped from an Orange County jail Friday.

The three inmates include Hossein Nayeri, 37, Jonathan Tieu, 20, and Bac Duong, 43, who all escaped from the Orange County Central Men's Jail located in Santa Ana. They were last seen at 5 a.m., and they were discovered to be missing at 9 p.m., Orange County Sheriff's Department spokesperson Lt. Jeff Hallock reported Saturday, according to The Guardian. The department noted that this was the first incident of prisoners escaping in their premises in a span of 20 years.

The inmates escaped by cutting through steel bars and passing through plumbing passages. After they located an unstable part of a roof, they used this as an entryway to rappel until they reached the jail grounds, Hillock added, ABC 10 News reported. They were on foot when they escaped.

The three escapees are charged with violent crimes. Nayeli has charges of kidnapping, torture, stealing and aggravated mayhem, while Tieu has charges of murder, attempted murder and shooting. Duong, the eldest of the three, has charges such as attempted murder, firearm and stolen property possession, theft and assault.

Sheriff Sandra Hutchens said that the department is collaborating with other agencies, such as the FBI and the U.S. marshals, for a manhunt of the prisoners.

"I am confident that this collaborative effort will result in returning these inmates to where they belong- behind bars," Hutchens said, according to Fox News.