JERSEY CITY, N.J. (CBSNewYork) — Six people were in critical condition Thursday following exposure to carbon monoxide in Jersey City.

Officials evacuated a 16-family residential building at 168 Harrison Ave. in Jersey City.

Officials say a carbon monoxide leak caused by the boiler in the basement is the cause. More specifically, a worker says the flue pipe fell off somehow, CBS2’s Alice Gainer reported.

Nearly a dozen people including a Jersey City firefighter were taken to the hospital due to exposure.

The injured include a pregnant woman, two teenage girls, a 13-year old boy, a 44-year-old man and a 40- year-old woman, 1010 WINS Al Jones reported.

While many got out safely, several people were passed out on the first floor, Gainer reported.

“Three people had to be carried out. They were unconscious,” said resident George Pinckney.

Though many residents said their carbon monoxide detectors were working, the city said two units didn’t.

As CBS2’s Valerie Castro reported, the company that runs the property could be in trouble.

“The City has aggressively inspected dozens of Trendy Management properties and issued more than 1,000 violations for housing, heath and fire code violations over the past several months,” said the Jersey City mayor’s office. “As for this particular address, four building code violations were issued in April and on re-inspection in May had been abated.  With regard to today’s incident, the fire inspector found two units that were in violation with no working CO or smoke detectors, and will be issuing violations to the building management. Additionally, as the building’s boiler malfunctioned and caused the carbon monoxide exposure, it has been red-tagged and put out of service until a plumber can repair.”

Trendy runs the property and dozens of others in the area.

“Too many times I complain. I complain because I have problem in my apartment,” Nasr Sadek said.

Sadek has lived in the building some 30 years, and said the issues started when Trendy took over the property last year.

“They don’t seem to care much about their tenants at all,” Diane Maxon added.

Maxon is with Jersey City Together, a group that advocates for tenants they say are bullied by management.

Sadek said repairs take too long to fix, and the company has taken him to court for disputes over his rent.

Maxon said it’s a scare tactic.

“They would lose people’s rent checks and then take them to court over and over for late rent when they were current on their rent,” she said.

Residents said they didn’t experience problems with the old management company.

The city said it will continue to investigate complaints at properties owned by Trendy Management.

CBS2 reached out to Trendy Management for comment, but did not hear back.