Several children rushed to hospital after carbon monoxide leak at Pennsylvania daycare

More than 20 children have been rushed to hospital after a suspected carbon monoxide leak at a nursery in Allentown, Pennsylvania.

The incident has been reported as a level 1 mass casualty, meaning that medics and emergency responders could be overwhelmed by the number of patients.

A number of children have fallen ill after the leak on Tuesday morning at Happy Smiles Learning Center on Wabash Street.

Allentown Fire Department Captain John Christopher confirmed that 25 children were in the daycare and that they will be assessed by medical professionals.

A few of the  parents took their own children to the hospital, while others were being triaged outside of the building. 

It is not clear how severe the injuries or illnesses are, with the most severely impacted being transported first.

Every ambulance in the area was called to the scene, which has been designated as a level on mass casualty event

At the time of the leak there were eight staff in the building, but it is not clear if any have been taken to hospital.  

Capt. Christopher confirmed that a 911 call at 6:51am was initially a medical call for a child who was unconscious.

Firefighters were then alerted to the carbon monoxide leak by their air quality detectors when they arrived on the scene. 

He added that ‘every Allentown ambulance in use’ for the ongoing incident, with all of the children eventually being taken to hospital to be monitored. 

The center was then evacuated as multiple people were showing symptoms of carbon monoxide poisoning. 

A number of children have fallen ill after the leak on Tuesday morning at Happy Smiles Learning Center on Wabash Street

The incident has been reported as a level 1 mass casualty, meaning that medics and emergency responders could be overwhelmed by the number of patients

Children were removed from the property on stretchers, and are being taken to various hospitals across the Lehigh Valley.

Multiple emergency services, including ambulances and firetrucks, were on the scene.

A number of children were still waiting to be transported at around 8am according to 69 News.

Officials confirmed that parents have been notified of the incident, and authorities are working with daycare center employees to keep everyone informed.

Another nursery around the corner has opened up its facility to keep children safe and warm. 

This is a developing story.