Greensboro, NC – GREENSBORO, N.C. – Ten people are recovering from what investigators believe is carbon monoxide inhalation at the HAECO building in Greensboro.

Eight of them were taken to the hospital, according to officials.

While crews are working to confirm the cause, the Greensboro Fire Department believes a natural gas heater in a paint booth at the HAECO building may be the cause.

HAECO provides commercial jet maintenance, repair and aircraft storage services from multiple locations in North America.

The call came in around 2:45 a.m. Thursday. Authorities said there were 30 people inside the building at the time.