A group of firefighters and police endured some pretty scary moments overnight when their search and rescue boat capsized in the cold waters of a river near Valleyfield.

The four firefighters and one police officer were sent out into the St-Charles River at around 1 am after a group of boys aged 10 to 12 told their parents they had seen a body in the water while playing there Thursday evening.

Surete du Qubec spokesperson Daniel Thibaudeau says while out in the water the rescue workers' boat hit a strong current and flipped over. 

"They were in the water for about 20 minutes when another one of our police officers was passing by and heard the screams coming from the water. He managed to pull them to safety."

Right in time too. Four of them are being treated for hypothermia. Their lives aren't in danger. 

Meantime, the search for the body the children say that they saw is resuming.