A massive manhunt is underway in Southeastern Pennsylvania, as officials say a "very dangerous" prisoner escaped from a Chester County prison on Thursday.

Danelo Cavalcante, 34, was first reported missing around 8:50 a.m. on Thursday, after escaping from the Chester County Prison in Pocopson Township, according to the county's District Attorney.

Here's security footage of him leaving:

Chester County District Attorney
Chester County District Attorney

Cavalcante was convicted of first-degree murder earlier this month. Officials say that he stabbed and killed his ex-girlfriend, Deborah Brandao, in front of her children in April 2021.

Danelo Cavalcante Is "Extremely Dangerous"

He was sentenced to life in prison without the chance for parole. He is also facing murder charges in Brazil from a 2017 case, officials say.

“Danelo Cavalcante is considered an extremely dangerous man," Chester County's DA Deb Ryan said. "We are asking for the public’s help in locating him. He was last seen walking on Wawaset Road in Pocopson Township around 9:40 a.m."

He is a Brazilian man who fluently speaks Portuguese and Spanish and some English, officials say. He's about 5 feet tall and weighs 120 pounds. He was last seen wearing a white T-shirt, gray shorts, and white sneakers.

Do not approach the suspect if spotted, officials say. You should call 911 immediately.

"Law enforcement is doing everything now to locate him," Ryan tells the media.

It's unclear how he escaped at this time, but an investigation is ongoing.

"Police, Detectives & Prison personnel are using every asset available, including helicopters and dogs, to find Danelo Cavalcante and won’t stop until he’s back in custody," officials tweeted early Thursday afternoon.

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