Inspector John Gordon said: “At around 10.25pm last night we received a report that a car may have entered the water at Muckros Pier on the Boa Island Road in Kesh, Co Fermanagh.
“A nearby police patrol responded and the two officers onboard spotted the vehicle in the water.
“Both immediately entered the lake and managed to free the woman from the sinking car.
“A third police officer who had arrived on scene also entered the water to ensure no one else was inside the vehicle.
“The woman was taken to hospital where her condition this morning is described as critical.
“I commend the brave actions of the police officers involved and my thoughts and prayers are with the female and her family this morning.”