Police today launched a murder investigation into the death of a two-year-old North-East boy who was found collapsed at his babysitter's home.

Kyle Fisher, who lived on the Central Estate, Hartlepool, Cleveland, died in the paediatric unit of Newcastle General Hospital on Friday.

Cleveland Police today called a news conference at its Ladgate Lane headquarters to urge the public to help their inquiry.

Detective Inspector Michael Wall, a child protection specialist, said Kyle had suffered severe head injuries.

''Emergency services had been alerted late on Wednesday night by his babysitter who claimed she found the toddler in a collapsed state at her home,'' he said.

''We are determined to find out how Kyle suffered his head injuries.''

Two women, aged 19 and 34, were arrested and have been bailed pending further inquiries.

Forensic tests have been carried out at three homes in the town.

Medical experts were trying to piece together how and when Kyle, an only child, died.

Mr Wall added: ''This is the death of a two-year-old boy from suspicious injuries.

''At the present time we are treating it as a murder inquiry and any help we can get from the public will be welcomed.''

Detectives want to trace a taxi driver who took a young woman to Hartlepool General Hospital after she had a night out in the town on Wednesday.

Anyone with information is asked to call 01642 302126.