Federal Authorities in the U.S.A. are conducting round-the-clock air monitoring to ensure the health and safety of all 5,000 residents of East Palestine village in Ohio after 11 of 20 train cars carrying toxic chemicals derailed, causing a fire two weeks ago. The train left its tracks because of a broken axle, investigators said.

The chemicals released into surface waters, the air, and soil included butyl acrylate, vinyl chloride, ethylene glycol monobutyl ether, and ethylhexyl acrylate. Phosgene, one of the chemicals released, was used as a chemical weapon in World War 1.

Crews from Norfolk Southern, the firm that runs the rail service, breached five tankers carrying vinyl chloride and diverted the substance to an excavated trench.

They then conducted a controlled detonation to avoid an explosion, emitting black noxious clouds in the area.

No one was injured in the incident. Over two thousand residents of the village who were evacuated because of health concerns related to the chemical leak have since been allowed to return home.

An administrator with the Environmental Protection Agency, Michael Regan, said the department “has not found any levels of health concern” in air monitoring conducted since the fire was put out.

He said the department would be around “as long as it takes to ensure the health and safety of this community, and that Norfolk Southern will be responsible for the costs and cleanup.

Karine Jean-Pierre, the Whitehouse spokesperson, said that Mike DeWine, the Ohio Governor, wanted to have more public health assessments and tests. The February 3rd fire damaged 12 additional cars, the National Transportation Safety Board said in a statement.