A survivor of the Portland apartment building fire that killed six people nearly two years ago testified Tuesday that a rear stairwell was blocked by a book case, forcing him and two others to escape through a second floor window as the fast moving fire filled a hallway with smoke and heat.

“I could only see partially down the hall. There was heavy black smoke on the ceiling,” said Paul Garrido, a 25 year old Rockland resident who was visiting friends. Garrido described hearing others in the house screaming as they tried to escape the thick smoke and intense heat.

“I shut the door to the bedroom to buy us some time,” he said. “The screaming continued. When the door shut, I could hear. One girl was screaming for help and the other was just screaming.”

Landlord Gregory Nisbet is in the second day of his trial on six counts of manslaughter – one for each of the young adults killed by the early morning fire. State prosecutors continued to press their Tuesday morning by questioning past tenants who survived the deadly Nov. 1, 2014 blaze about the condition of the building and their efforts to escape the fire.

Other potentially damaging testimony came Tuesday from a former contractor who did work on the house for Nisbet.

Waldo Trott, a self-employed home remodeler, testified that he told Nisbet years ago that he thought the third-floor windows were too small to be legal as an emergency exit and that he noticed that building had deteriorated and become “a slum.”

The fire was accidentally started when someone at the home improperly discarded smoking materials on the front porch.

A state prosecutors said Monday that Nisbet is responsible for the loss of life because he rented out substandard apartments that turned the rooms into “death traps.” Women were heard screaming from the third floor where they were trapped and unable to escape through the window, Assistant Attorney General John Alsop said.

Nisbet’s attorney on Monday defended the landlord’s management of the building and said the victims may have been incapacitated by the heat and gases and unable to use emergency exits.

The fire’s victims included Steven Summers, 29, of Rockland, Maelisha Jackson, 23, of Topsham and Chris Conlee, 25, of Portland, who were visiting the house. The fire also killed house residents David Bragdon Jr., 27, Ashely Thomas, 26, and Nicole Finlay, 26.

Paul Garrido, who was sleeping on the downstairs couch, testified Tuesday that he was woken up by someone screaming, “Fire!” and by the banging and popping noises of the fire.

He smelled smoke and saw the front door engulfed in flames. He grabbed his coat and overnight bag, but only had time to put on one shoe before trying to escape.

With the front door engulfed, he ran upstairs, yelling and banging on the walls to alert other residents of the fire, he said. At the top of the stairs, resident Nathan Long ran past him and began to clear off a bookshelf that was blocking a rear exit.

Garrido said Long shook Kyle Bozman to wake him up, then all three escaped through the window. Garrido estimated it took him about 90 seconds from the time he woke up to get outside and that he heard the women screaming for about the last 30-40 seconds. A prosecutor said Monday that the women living on the third floor were trapped because there was no emergency exit.

During cross examination, Defense attorney Matthew Nichols sought to highlight inconsistencies with Garrido’s testimony.

Nichols noted that Garrido told a deputy fire marshal that there was one woman screaming and that it was Maelisha Jackson. He also told police that Steven Summers had jumped from a second-floor window to escape, although Summers actually ran out the front door. He was burned so badly that he died several days later.

Garrido said that, in hindsight, he should not have speculated about who was screaming and that he did not know for sure how Summers escaped.

During the graphic testimony, Summers’s mother wiped away tears and was comforted by Ashley Summers, Steven’s wife.

Nathan Long also testified about the moments of trying to escape the fire.

Long’s second-floor bedroom overlooked the front porch where the fire started. He woke up to his alarm at 7:15, around the time the fire was spreading.

“There was fire right outside of the window,” Long said. The intensity of the flames prevented him from opening the door to David Bragdon’s room across the hall, he said, and he couldn’t get down the stairs because of smoke and flames.

Long ran down the hall to wake up Bozman, then tried to clear the back stairwell before ultimately escaping through Bozman’s window about a minute later. He said the presence of smoke forced him to leap to the ground from the porch roof, even though he thought it was too high.

Long said he did not hear anyone screaming as he rushed to escape the house.

He placed a 9-1-1 call at 7:17.

Long said there were no smoke detectors in the apartment and he never saw Nisbet inspect the apartment when new tenants moved in.

However, Long also said he considered all of the tenants to be a single family, even though they paid their rents separately and used padlocks on the outside of their bedroom doors. He also noted that occasionally, people took up residency in the basement and at one point in a van outside, to which electricity was supplied by an extension cord.

Long said Bozman had been sleeping on the downstairs couch for about a month, while waiting for a previous tenant to remove belongings from his room. Bozman moved the items to the back stairwell a few days before the fire, he said.

During cross examination, Nichols attempted to highlight the speed at which Long escaped. He also highlighted the fact that Long, like Garrido, considered themselves to be sober when going to bed, making it easier for them to escape.

Trott, the home remodeler, said Nisbet brushed off his concerns about the size of the third floor window when he brought it up in late 2007 or early 2008. At the time, Trott was rebuilding the back porches of the Noyes Street house as well as doing regular maintenance.

“I didn’t know anybody was up there. I just thought they were small,” he said, estimating that the window was two feet wide by three feet long. Only half of the window could be opened at any time.

Trott said he never reported the small windows to the city codes office. Nor did he contact authorities after he learned that people had died in the fire. The subject came up when he was being interviewed by an investigator for the state fire marshal’s office.

Trott, who stopped working for Nisbet about a year later, said he frequently observed the deteriorating condition of the house when he stopped for coffee at a nearby convenience store. “It went from pristine to what I say is a slum,” Trott said.

A state prosecutor argued during the first day of the trial on Monday that Nisbet operated 20-24 Noyes St. as a rooming house without the necessary fire alarms or emergency exits. Assistant Attorney General John Alsop also said Nisbet deferred maintenance on the building after he stopped paying his mortgage in 2011 and faced foreclosure. Alsop said that although Nisbet continued to collect rent and take on new tenants, he did not conduct regular inspections that would have revealed a lack of smoke detectors and blocked rear stairwell.

Nisbet also faces charges of five violations of the Life Safety code, including not getting a building permit to add two bedrooms on the third floor, where three residents died. Prosecutors say the tenants were heard screaming during the fire and would have survived if there had been an escape route.

Nichols, however, claims that Nisbet was running the duplex as two single-family homes and that the building did not meet the definition of a rooming house. He said Monday that city code allows up to 16 people to live under one roof and still qualify as a family.

Nichols also suggested that victims were quickly incapacitated by heat and gas and would have been unable to escape even though they may have been alive as the fire spread through the house.

A fire consultant from the U.S. Bureau of Alcohol Firearms Tobacco and Explosives gave the court a detailed accounting of the timeline of the fire. He said heat and gases reached the third floor in less than a minute after the front door was opened by Summers as he tried to escape.

If convicted, Nisbet would be the first landlord in the state found guilty of manslaughter for an accidental fire.

Nisbet waived his right to a jury trial, so the case will be decided by Justice Thomas Warren.

This story will be updated.