A man arrested on suspicion of murder of a mother and her nine month old baby at a house in Birmingham is being assessed by mental health experts.
The victims, named locally as Yvonne Walsh, 25, and her son Harry, were discovered in a terraced house in Billesley, Birmingham, at about 10.30am on Sunday.
The suspect a 28 year old male was arrested by the police around seven hours later in the Sandwell area of the West Midlands. It was confirmed the man was known to the victims.
A police spokesman said the victims are yet to be formally identified but are believed to be Yvonne Walsh and her son Harrison Walsh.
The man arrested on suspicion of both murders has been sent to a secure facility following an assessment by mental health professionals.
He is currently deemed unfit to be interviewed by officers at this stage, but this is being constantly reviewed.
The person in custody was known to the victims and officers were keen to stress that they were not looking for anyone else in connection with the killings.
Post-mortem examinations were due to take place later to determine the cause of the victims' deaths.
A police cordon remained in place on Monday at the entrance to Chells Grove, where the pair's bodies were discovered after concerns were raised for their welfare.
A police van was also parked near the head of the cul-de-sac as forensic inquiries continued at the scene.
One resident leaving the street said police had initially informed local people that a serious incident had taken place in the street. Declining to give her name the neighbour said they saw Ms Walsh around with her little baby but she kept herself to herself.
She added that it was surprising that such a thing had happened when she had not heard nor seen anything happening at the house before.
It was only after the police had arrived the next morning when the seriousness of the incident became evident she said.
Police are not looking for anyone else in connection with the killings.