Here's how convicted killer Danelo Cavalcante escaped from prison, according to sources. He's still on the run.

Chester County, Pa. — Danelo Cavalcante, the fugitive convicted murderer, escaped from the Chester County Prison last week by climbing up to the roof, multiple sources told CBS News Philadelphia Tuesday night. 

He escaped on Aug. 31 at around 8: 30 a.m.

Officials have remained tight-lipped on how Cavalcante broke out.