Behind a metal door at a ground floor apartment on Bainbridge Street in Bed-Stuy Brooklyn, NYPD detectives say a woman suffered unspeakable punishment; at the hands of her ex-boyfriend, 31-year old Anthony Matthews.

He is now under arrest.

Ruby Moses, who lives in the upstairs apartment right next door, told PIX 11's Jay Dow, "It's horrible that that happened to that young lady. It's beyond words that someone could be next door and I not know anything."

Law enforcement sources tell PIX 11 that over the period of a month and a day – beginning on Friday, June 29th, Matthews subjected the woman to unspeakable acts of torture.

She's now in bad shape at Woodhull Medical Center.

Matthews allegedly burned her with a hot iron, sexually assaulted her with burning hot screwdriver, beat her with a 2x4…and knocked out at least two of her teeth while shoving a pistol in her mouth.

Police say Matthews dropped the woman off at his mother's house Tuesday, while sources say he feared she was going to die of her injuries.

Police Commissioner Ray Kelly says from that home, the woman then ran for her life and that's how she ultimately made it the hospital.

Neighbors say police cornered Matthews at his home on Wednesday.

Ron, who did not want to give us his last name, said, "They got up on the roof and that's when the guy came out at the gate over there."

Records show Anthony Matthews previously served 11-years in Attica state prison for assault, criminal possession of a weapon, and reckless endangerment. For this latest incident – he now faces those same charges, and new one – kidnapping.