A man has been arrested in connection with the death of a three-week-old baby following a dog attack.
The boy - named locally as Reggie - was rushed to hospital early this morning from his home in Sunderland but died later.
Flowers have been left outside the semi-detached house in Falkland Road with tributes and messages of support.
A relative said the boy's mother returned from a family event in the early hours to find a terrible scene. He wanted to stress that although the baby's mother was out, the youngster had not been left alone.
The man, who did not want to be named, said the dog - said to be a small terrier-type animal - was usually kept outside, in an outhouse, and was never left alone with the children. He described it as a good natured animal.
He said the family was devastated and wanted to know how the attack could have happened.
Northumbria Police said the dog has been removed from the address and is likely to be destroyed. Officers stressed it no longer posed a danger.
A spokesman said a 30-year-old man had been arrested in connection with the incident and is helping police with their inquiries. He confirmed the man was inside the property at the time of the incident.
He said officers were called to the property at 4.15am today.
Superintendent Gillian Mitchell said: "Our thoughts are with the family of the baby at this difficult time. We have officers supporting them and will continue to do so throughout our enquiries.
"We recognise this incident is concerning for residents and officers will remain in the area to offer residents reassurance and answer any questions they may have.
"The family dog was quickly taken from the house and is now in secure kennels."
She said: " We are carrying out enquiries to establish the circumstances of the incident and will have extra officers in the area to allow this to be done.
"Officers will also be on patrol to offer reassurance to the local community who may be concerned."
A number of bunches of flowers have been laid against the front wall of the house in the quiet, tree-lined street.
Some were accompanied with messages of support. One said: "Thoughts with you and all the family".
The blinds of the pebbled-dashed, three-bedroom semi-detached home were drawn this afternoon and the only sign of any incident was the police presence outside. Children's toys could be seen outside the back of the property.
Uniformed police were patrolling in the area and a police van was parked directly outside the front of the property.
A woman, believed to be the baby's grandmother, went in through the front door still wearing her pyjamas earlier, accompanied by plain-clothed police.
She emerged again after about ten minutes and was driven away by the officers, clearly distressed.
Neighbours said they were shocked by what happened and said the mother, who has two other children living with her, had been overjoyed by the baby's recent birth.
One told the BBC: "I know what I feel like and she must be worse. It's such a shock. I can't get over it."
Neighbour Paul Tweddle said: "Words won't console them with what they're going through. Their baby's only three weeks old.
"They were such a proud mam and dad. They've got a few children between them - very family orientated.
"They're a run-of-the-mill, nice family."
Mr Tweddle said: "It's just horrible. It is a big shock. Eveybody sort of knows everybody. I'm a dad myself. You just can't imagine. It's really, really horrible."
He said he had not seen baby Reggie since he was born but he saw the mother recently and asked her if she was having sleepless nights.
Mr Tweddle said she told him the new-born was a good sleeper.
He said: "It's terrible, it's horrible, what do you say?"
As well as flowers outside the house, local children placed cuddly toys, including a large white polar bear, a turtle and a Scooby Doo figure.
One tribute said: "Our thoughts and prayers are with you at this tragic time.
"Shine like a bright diamond little one. Beautiful boy gone too soon."