Premature twin baby girls have died and their mother lies seriously ill in a Birmingham hospital after paramedics were prevented from getting inside their flat.

Melody and Rose’s life support machines were reportedly switched off on Tuesday. Their mother 27-year-old Jocelyn Bennett, who remains in hospital in a coma after her heart stopped and she suffered severe blood loss, is unaware of what has happened, her family told the Birmingham Mail.

West Midlands ambulance service said it was called to the Pleck House flats in Winterbourne Croft at 5.39am. A paramedic arrived 12 minutes later but had difficulty getting into the building.

The newspaper reported that Bennett, who was 32 weeks pregnant, dialled 999 after suffering severe stomach pains but was in such agony she was unable to let paramedics into the block. They tried other buzzers, but got no response.

Bennett’s partner, Kevin Clarke was away from home at the time.

The police managed to get access to the block at 6.10am, 31 minutes after the first 999 call, when paramedics were then able to start treatment.

Birmingham city council, which owns the flats, said it had systems allowing emergency services access and an urgent investigation was under way to find out what had happened.

Bennett’s family said she suffered a placental abruption resulting in her prematurely delivering Melody, while Rose was delivered by emergency caesarean later at hospital. However, the babies suffered multiple organ failure.

Bennett’s father Joe Bennett told the Birmingham Mail: “[The twins] looked so perfect and when the ventilators were taken off their tiny bodies, I expected them to start moving.

“The vicar performed a lovely service and then the girls were held by Kevin for the last time. We left him with the twins so he could spend time with them on his own.”

The ambulance service said: “Crews had difficulty getting into the building. They tried to contact all of the other flats within the block, all with no answer. The control room contacted the patient’s parents and partner by telephone.”

A city council spokesman said: “Our thoughts are with the family at this difficult time.

“We have systems to provide emergency access to our blocks for the emergency services and an urgent investigation was commissioned as soon as we were made aware of the matter.

“The ongoing investigation will involve all other agencies concerned.”