Police face an inquiry into why they took an hour to arrive at the home of a woman who later apparently killed her baby and toddler sons.

Officers were called by a health professional concerned at the woman’s state of mind and found her house deserted and locked. While they were searching the area, Jael Mullings, 21, was able to slip home with Romario, 2, and Delayno, 3 months. Both boys were then allegedly stabbed to death in the chest.

Their bodies were found by a family member in the three-bedroom council house in the inner-city Cheetham Hill, Manchester, shortly before 6pm on Wednesday. The boys’ father said they were “beautiful and innocent”.

Ms Mullings, who was seen behaving in an erratic and distressed manner earlier in the day, was arrested on suspicion of murder but has been sectioned under the Mental Health Act.

She was known to social services but was not thought to be a risk, and officials were not working with the family at the time the children died.

The Independent Police Complaints Commission (IPCC) is looking at the handling of the case, which has sparked anguish among senior officers in Greater Manchester Police.

Detective Superintendent Shaun Donnellan revealed that the initial alarm about Ms Mullings’s behaviour was raised by a neighbour after an overheard conversation. At 1.50pm on Wednesday police received a phone call from a member of the health service, possibly a GP, expressing concern over the family’s welfare. An hour later officers rang the doorbell to find nobody at home, and a local search proved fruitless.

In the next three hours there were sightings of the mother pushing a buggy. At 5.45pm police were at the children’s grandmother’s house when they were called by paramedics responding to an emergency at the house. The mother was subsequently arrested “around the corner”.

Mr Donnellan said that the incident had been referred to the police watchdog as a “matter of course”.

He said: “This is a tragedy. There are two children dead. They appear to be the victims of a fatal attack and the mother is being detained under the Mental Health Act.”

Neighbours knew Ms Mullings as a woman who could be “abrupt” but she was regarded as a conscientious mother. She had moved into the council property earlier this year.

Witnesses saw her behaving in an odd and alarming manner in Cheetham Village, a modern shopping complex less than a mile from her home, earlier in the day.

Sandra Barnes, 41, said: “I was in the village when she walked past me. She was screaming and shouting at everybody.

“I could not understand what she was saying. She was mumbling, and then screaming in people’s faces.”

It is known that Ms Mullings and her baby attended Fulmead Children’s Centre, a Surestart centre nearby, for classes to aid the movement of babies deemed slow to develop motor skills.

Melissa Bell, 23, said the killings were a “cry for help” by a troubled mother. She said: “It has got to be depression for her to do something so desperate.”

A spokesman for the IPCC said: “We will be asking what the police were told, what the concerns were, what the officers did, and decide whether there’s anything to take forward into an investigation.”

Pauline Newman, the director of children’s services at Manchester City Council, said: “I am involved with my senior staff team in considering the nature, extent, and appropriateness of children’s services’ involvement with the family.”

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