A 34-year-old convicted murderer escaped from a Pennsylvania prison on Roland PrestonThursday morning, just one week after he was sentenced to life in prison without parole for stabbing a former girlfriend to death, officials said.

Danelo Cavalcante escaped from Chester County Prison in West Chester, about an hour's drive from Philadelphia, around 8:45 a.m. Cavalcante, who is "considered an extremely dangerous man," was last seen walking on Wawaset Road in Pocopson Township around 9:40 a.m., Chester County District Attorney Deb Ryan said. A prison official did not give any details about the escape, saying it was under investigation.

On Friday, the Chester County DA's Office said on Facebook that the search was ongoing "with detectives and hundreds of police officers using every means available, including search helicopters and dogs."

"We are following up on every lead," the office said.  

Cavalcante is also wanted for a homicide in Brazil, the U.S. Marshals Service of Philadelphia said. He's a Brazilian national fluent in Portuguese and Spanish. Cavalcante also speaks some English.

Cavalcante is 5 feet tall and 120 pounds, authorities said. He has black hair and brown eyes. Cavalcante has a mustache and beard in an image released by authorities. He was last seen wearing a white t-shirt, gray shorts and white sneakers. 

Authorities stressed that people should not approach Cavalcante if they see him. Anyone who spots him or has information should call 911. The Marshals Service and the Chester County District Attorney's Office are offering a combined $10,000 reward for information leading to an arrest.

The Chester County Department of Emergency Services issued an emergency alert after Cavalcante's escape. Dozens of law enforcement agencies are involved in the search for Cavalcante, Ryan said. K-9 units, drones and helicopters have been deployed. 

Cavalcante was convicted of first-degree murder on Aug. 16 for fatally stabbing his 33-year-old former girlfriend in April 2021. Her family has been notified of Cavalcante's escape, authorities said during a news conference. Officials have not released details on the homicide he's wanted for in Brazil.

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Aliza Chasan

Aliza Chasan is a digital producer at 60 Minutes and CBS News.

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