Three people are said to be in critical condition after a carbon monoxide leak at an Aspen Hill apartment building.
The leak was detected at the Garden Style Apartments at 14200 Wolf Creek Place in Aspen Hill.
Montgomery County Fire and Rescue said three patients had become ill from the gas. They are said to be critical condition and are being transported to a hospital.
The three patients live in a bottom unit where the leak originated. The carbon monoxide level reached over 700 parts per million at one point, dangerously high.
Firefighters evacuated the building, rushing families out of their homes.
"We don't have a lot of information," resident Yari Pilorio said. Pilorio, who has three children, was "not sure when we will be able to return to our apartment... We're just going to wait here and see what happens."
It's believed the problem started with a faulty furnace, a reminder to residents to be cautious as nights turn cold and heaters are kicked on for the first time, said Montgomery County Assistant Fire Chief Mike McAdams.
Laura Chaco rushed to the store to buy a CO detector Friday.
"It's scary, a looked around my unit and realized I didn't have (one)... Ironically this happens," she said.