MINNEAPOLIS (WCCO) — A fun morning outside turned into a life-threatening emergency at one west metro daycare after a toddler was found unresponsive on a Twin Cities playground.

A source tells WCCO-TV a 2-and-a-half-year-old girl was trying to get up to the monkey bars at New Horizon Academy on Hyland Greens Drive in Bloomington when the strap of her bike helmet became tangled in a ladder.

When first responders arrived there just before 10:30 a.m. Thursday, she didn’t have a pulse. She was rushed to the hospital.

Since 1999, the Bicycle Helmet Research Foundation says three children in the United States have died wearing helmets while playing.

The U.S. Consumer Product Safety Commission has warned of this hidden helmet hazard before. The agency recommends that kids should never wear helmets while on playgrounds or climbing trees because the strap can get caught, and the helmet can entrap a child’s head.

A properly-fitted helmet is key when kids are enjoying other summertime activities like biking, roller-skating or scootering.

After measuring your kid’s head and selecting the right size, you want to make sure the ear straps on the side of the helmet come down in two Vs, according to the UVA Health System. No more than two fingers should be able to fit in between the chin strap and the child’s chin.

At last check, the girl was listed in stable condition at Children’s Hospital.

After the incident, New Horizon Academy sent WCCO-TV the following statement:

This morning, a child suffered an accident on our playground which required the support of emergency medical personnel. Our staff responded swiftly to the child’s injuries, first responders were quickly on site, and the child was transported to a nearby hospital for further medical care. At this time we do not have additional information to share. At New Horizon Academy, the safety of our children is our first priority.