California officials have launched an intense manhunt to track down three "dangerous" inmates who escaped from a maximum-security jail in Southern California on Friday.

The men cut through half-inch steel bars and used plumbing tunnels to access an unsecured roof at the Orange County Central Men's Jail in Santa Ana -- about 40 miles from Los Angeles, reports The Chicago Tribune. They then rappelled from the roof to the ground using a makeshift rope.

"It was very well-thought-out and planned," Orange County sheriff's Lt. Jeff Hallock said Saturday at a news conference.

The three inmates, which includes a murder suspect, were last seen at 5 a.m. on Friday. Authorities then noticed that they went missing later that night during a head count around 9 p.m.

During a press conference on Sunday, Orange County Sheriff Sandra Hutchens urged people not to approach the men if they appear in public.

"Each of the three should be viewed as very dangerous. We don't have any specific information that they are armed, but I think the public should expect the worst if they're encountering them and call 911," Hallock said, according to authorities told CNN affiliate KABC.

The men have been identified as 37-year-old Hossein Nayeri, 20-year-old Jonathan Tieu, and 43-year-old Bac Duong.

Hossein faces charges for kidnapping, aggravated mayhem, torture and burglary. He has been in custody since September 2014.

Tieu is accused of murder, shooting at an inhabited home, gang activity and attempted murder. He was held on a $1 million bail and had been in custody since October 2013.

Duong also faces a host of difference charges, the most serious being attempted murder. He was taken into custody last month and held without bail due to an immigration hold.

Orange County Sheriff Sandra Hutchens released a statement ensuring that her team was working around the clock with the district attorney's office, the probation office, U.S. marshals and the FBI to find the men.

"I am confident that this collaborative effort will result in returning these inmates to where they belong -- behind bars," she said. "We are utilizing every resource available to ensure these inmates are brought back into custody as quickly as possible," she added.

The FBI is offering a $20,000 reward to anyone who provides information that leads to the arrest of any and all escapees. Meanwhile, the U.S. Marshals Service is offering an additional $30,000 for info leading to the arrest of the accused felons, reports The Orange County Register.