UPDATE: Man arrested in connection with fatal Pasadena fire released

PASADENA -- A man arrested in connection with an apartment fire that killed a 28-year-old Pasadena woman has been released from jail pending further investigation, authorities said Tuesday.
Corey Green, 28, of Los Angeles was released from jail Monday afternoon, according to county booking records.
The body of Maria Donnely was found inside her apartment in the 000 block of South Meridith Avenue after firefighters extinguished an early-morning blaze, police and fire officials said.
Originally booked on suspicion of murder Sunday, detectives released Green pending further investigation, Pasadena police Lt. Tom Delgado said. A case was not presented to the Los Angeles County District Attorney's Office for prosecution.
"This is a very complex investigation," the lieutenant said.
Green remains a "person of interest" in the investigation, he added.
"Detectives are doing their investigation and will follow up any leads that they develop," Lt. Phlunte Riddle said.
Officials said Green was believed to be Donnely's ex-boyfriend.
The cause of the fire has been ruled to be arson, Riddle said.
The exact manner in which the blaze was sparked was not clear Tuesday, she said, "but (fire investigators) do know that is was intentionally set."
Pasadena police investigators have said Donnely's death was a homicide, though coroner's investigators have not yet determined Donnely's specific cause of death.
She had suffered "blunt force trauma" prior to the fire, Lt. Phlunte Riddle said, though she declined to discuss the injuries in detail due to the ongoing investigation.
Donnely was likely dead, "or at least unconscious," when the fire broke out.
The specific cause of death remained unknown pending further examination, Los Angeles County Department of Coroner Assistant Chief of Operations Ed Winter said.