Published: Jul 31, 2012 10:18 AM EDT
Updated: Jul 31, 2012 12:36 PM EDT

SANIBEL, Fla.- A 2-year-old boy is in critical condition after nearly drowning on Sanibel Island Monday evening.

Bystanders found the child unresponsive in a pool at the Sanibel Arms Condominiums just before 9:30 p.m. They performed CPR until medics arrived, authorities say.

The child was brought to HealthPark Medical center, where he was placed on a ventilator.

The toddler, who is expected to turn 3 next month, was visiting Southwest Florida with his grandparents. His parents were at their home in Louisiana at the time of the accident, according to Sanibel Fire officials.

A family friend who witnessed the incident says the child pulled off his water wings, causing the near-drowning event.

Police were on scene Tuesday morning questioning witnesses.

The Sanibel Police Department says it is an open investigation, but it does not appear to be a suspicious situation.