She returned to find Dontay Lau, two, face down in 10 to 12 inches of water. He was in a plastic container that was being used to bath him at the family home in Claygate Drive, Blackley.

Alicia Lau, 20, told a Manchester inquest she was bathing the tot when he had a tantrum because the water was cold. She had to go downstairs to heat some more because the boiler had broken down.

She sobbed as she told the inquest: "I grabbed him and called the ambulance service, and they told me what to do until help arrived.

She told how, although the water was warm, she had decided to get some more. "I had no concerns about leaving him. The container, which was in the bath, was too small for him to lie down, and I had left him before for short periods."

Quizzed by Deputy Coroner Simon Jones, Miss Lau said she had only been away for five to 10 minutes.

"When I returned, I saw Dontay had slipped and was lying face down in the water."

Paramedics got to the house within four minutes, but Dontay was pronounced dead at Booth Hall Hospital, one night in April last year.

Det Con David O'Toole said Miss Lau, now of Whalley Range, was interviewed under caution after allegations of wilful neglect.

"But the Crown Prosecution Service found no evidence of neglect and came to the conclusion it had been a tragic accident," said the officer.

Recording an accidental verdict, the Coroner said he `fully endorsed' the findings of the CPS.

"I agree that no blame should be attached to Alicia," added Mr Jones.

Accident prevention campaigners have said that children should not be left alone in or near water for any length of time.

A spokeswoman for the Royal Society for the Prevention of Accidents (RoSPA) said according to their most recent figures 57 children under the age of six had drowned in the bath between 1995 and 2005.

She said: "Sadly we do hear of children drowning in the bath at home. We have even heard of circumstances where the parents have been absent for just two minutes and it has caused serious damage to the child or they have even died.

"This case is obviously very tragic and we just hope it highlights that this does happen and we want to reiterate how important it is to supervise children near water or in the bath."

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