MINNEAPOLIS (WCCO) – Eagan police say a 5-year-old boy is still in the hospital after a near-drowning at a pool last week.

Eagan police and fire responded at about 10:20 a.m. last Tuesday to the Foxridge Estates Apartments on a possible drowning involving a 5-year-old boy. When authorities got to the scene, they found a construction worker performing CPR on an unresponsive boy near an outdoor swimming pool.

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Firefighters and paramedics continued treatment on the boy before he was taken to Regions Hospital. Eagan police said Tuesday the boy is still in the hospital, listed in serious condition.

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A preliminary investigation shows the boy and his sister were home at the apartment with their mother. At some point, the two children left the unit without the mother knowing. They walked to the pool, which is surrounded by a fence and secured by a locked gate. Authorities believe the boy climbed the fence to get access to the pool.

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Police say he somehow entered the water, and was found unconscious before being removed by a construction worker. Authorities say they don’t know how long the boy was under water, and his medical condition is not known.