Image caption The baby died at Royal Blackburn Hospital after she was mauled by a pet dog in Emily Street, Blackburn

An 11-month-old baby girl was killed by a "pit bull terrier-type" dog while asleep upstairs in bed, police said.

Ava-Jayne Marie Corless was taken to hospital from Emily Street, Blackburn, at 23:00 GMT on Monday where she died.

The baby's mother Chloe King, 20, and her boyfriend have been arrested on suspicion of manslaughter. They were downstairs when she was attacked.

Ava-Jayne was not at her home address but lived nearby. The pet, classed as a dangerous dog, has been destroyed.

Image caption Tributes have been left for baby Ava-Jayne in Emily Street, Blackburn which has been cordoned off

Ms King and her 26-year-old boyfriend Lee Wright, who is not the child's father, are also being questioned on suspicion of child neglect.

'Horrific incident'

A post-mortem examination will take place to find out the exact cause of Ava-Jayne's death.

During a press conference, Ch Supt Chris Bithell said: "This is an absolutely horrific incident in which a baby girl has lost her life."

Police were first alerted by the ambulance service who were called to reports of the girl being mauled by a pet dog.

"I'm told it's quite a large pit bull-type dog," Mr Bithell said.

"As part of the investigation we are making inquiries to see whether there have been previous issues with this particular dog," he added.

Image copyright PA Image caption Forensic officers are examining the house in Emily Street, Blackburn, where 11-month-old Ava-Jayne Marie Corless was killed by the dog

A Lancashire Police spokesman later confirmed that the dog was a "pit bull terrier-type dog prohibited under the Dangerous Dogs Act 1991".

The mother and boyfriend remain in custody, he added.

No-one else was injured during the attack.

A neighbour, who did not want to be named, said: "She was a lovely little girl, always smiling, always happy, just like her mum.

"It's sickened me to my stomach."