A neighbour today described the "frantic search" for twin toddlers who were found in a garden pond in Staffordshire.
The two-year-old boys went missing from their large gated home in the village of Tean on Monday evening.
Following a search by their worried parents and neighbours they were found in a pond at the back of a house near the family home in Breach Lane a short time later.
Ambulance crews said the toddlers would have died if a woman living nearby had not performed "first-class" first aid.
One of the boys remains in a critical condition at University Hospital of North Staffordshire in Stoke-on-Trent. The second boy is "stable but poorly", police said.
Neighbour Mark Deaville spoke of the desperate search for the boys.
Mr Deaville, district councillor for Staffordshire Moorlands, said: "The boys went missing at around 6pm. We don't know how they got out because we never usually see them out in the lane.
"We can hear them playing behind the gates but somehow they got out. There was a frantic search to find them, it was horrendous.
"Their dad thought they might have gone off down the lane or into a neighbour's garden.
"I don't know how they got out, the house is so secure. All the neighbours helped with the search. It was all hands to the wheel until they were found in the pond."
Mr Deaville declined to name the boys, but said their parents were devastated. He praised the actions of the woman who gave first aid, but declined to name her at this stage.
"She is definitely a hero," he said. "But she does not want to speak about it at the moment. "She is as upset as everyone else but she realises it is an important message to get out that first aid training is so vital."
Mr Deaville also praised the ambulance crews who were called to the scene at 6.25pm.
The boys' father looked devastated this morning as he collected the bins outside their home. With tears in his eyes, he said he was too upset to speak.
The woman who pulled the boys out of the water performed life-saving breaths and chest compressions until paramedics arrived.
West Midlands Ambulance Service spokesman Murray MacGregor said it was unclear how long the boys had been in the water and praised the woman for her "first-class" first aid.
Community Paramedic Officer Dave Quinn said: "Her knowledge of first aid has given both children the best possible chance of survival.
"Without her actions we would almost certainly have been looking at a double tragedy.
"If ever there was a demonstration of why everyone should know basic first aid, this must be it. This was a real team effort that has given two young boys the best possible chance of survival. However, without the woman who was doing CPR, none of the skills of the ambulance staff would have been of any use."
"This was an exceptionally difficult incident for us to deal with. Not only was it dark and damp, we were dealing with two very young children.
"Add to that, the level of information available at the time about what had happened was limited."
A Staffordshire Police spokesman said the force was alerted by West Midlands Ambulance Service.
"The incident concerned two young children who had been discovered in a pond and are now being treated at the University Hospital of North Staffordshire," he said. "The first is said to be in a critical condition. The second child taken to hospital is in a stable, but poorly, condition.
"We are treating the incident as a tragic accident and are offering support to the family at this very difficult time."