Three inmates charged with violent crimes have escaped from a maximum security jail by cutting through steel bars and abseiling from the roof, it was reported.

Jonathan Tieu, Hossein Nayeri and Bac Duong escaped from Central Men's Jail in Santa Ana, around 40 miles southeast of Los Angeles, at some point on Friday.

Tieu, 20, who is charged with murder, attempted murder and "shooting at an inhabited dwelling" has been held in the jail since 2013. His case is believed to be gang-related.

Nayeri, 37, has been held since September 2014 on charges of kidnapping, torture, aggravated mayhem and burglary.

He and three other men are accused of kidnapping the owner of a California marijuana dispensary owner in 2012. They drove him into the desert where they believed he had hidden money - then burnt him with a blow torch, cut off his penis and doused him in bleach, according to court documents.

After the alleged crime, he fled from the US to his native Iran. In November 2014 he was arrested in Prague while changing flights from Iran to Spain, where he was going to visit family.

Bac Duong, 43, has been held without bail for a month. He faces charges including attempted murder, assault with a deadly weapon and shooting at an inhabited dwelling, as well as being an ex-felon on possession of a firearm and other charges.

Jonathan Tieu, 20, is charged with murder (Orange County Sheriff's Department)

Hossein Nayeri, 37, is charged with kidnapping and torture (Orange County Sheriff's Department)

Bac Duong, 43, is charged with attempted murder (Orange County Sheriff's Department)

The trio were last seen at 5am on Friday.

"It was very well-thought-out and planned," KTLA5 reported Orange County sheriff's Lieutenant Jeff Hallock saying.

"The inmates cut through half-inch steel bars to facilitate their escape."

They also cut through plumbing tunnels to reach an unguarded area of the roof.

Once there, they pushed aside barbed wire and used a "makeshift rope" - possibly from sheets or clothing - to abseil to the ground.

It was unclear if they had any assistance from anyone outside the jail, Lieutenant Hallock added.

Lieutenant Hallock said the public could "expect the worst" if encountering them.