A toddler who fell into a garden pond in Bicester was last night still fighting for his life as experts warned parents to be extra careful in the hot weather.

Two paramedics from the Oxfordshire Ambulance NHS Trust resuscitated the 18-month-old boy after he fell into the pond at a house in the centre of Bicester at about 3.30pm on Monday.

Ambulance spokesman Helen Robinson said the child was unconscious, his heart had stopped beating and he was not breathing when paramedics arrived.

She said they resuscitated him before he was taken by ambulance to Oxford's John Radcliffe Hospital.

Ms Robinson added the child had not regained consciousness while in the care of ambulance staff. She believed the toddler had been in the water for more than two minutes, but no longer than 30.

Roger Vincent, spokesman for the Royal Society for the Prevention of Accidents (Rospa), said on average eight children under five drowned in garden ponds every year.

Mr Vincent added that in about 80 per cent of cases, children drowned in ponds in other people's gardens.

He said: "When you get these spells of hot weather, children are more likely to be out and about in the garden, and tragedies like these are likely to increase."

Mr Vincent said ponds should be filled in or covered up when children were around.

But he added: "Sometimes children have drowned in the rainwater collected in the top of covers.

"Sometimes their faces have gone through the wire mesh.

"The only 100 per cent safe thing to do is not have a pond when you have a small child."

A John Radcliffe spokesman said the 18-month-old boy was in a critical, but stable condition yesterday.