A BBC Wales investigation to be screened on Wednesday will highlight a stark warning that child protection services in Cardiff are in crisis.

The investigation by the Week In Week Out programme has discovered disturbing new evidence of the severe pressures facing frontline social services in the city.

Sir Ronald Waterhouse, who chaired the North Wales child abuse tribunal, has also warned that unless more money is put into child protection nationally, lives will be put at risk.

Sir Ronald told BBC Wales: "It seems whoever is in power there is a lack of will or a lack of belief that there's the need for further financial provision and I think it's wrong".

Asked whether he felt that children remained at risk Sir Ronald said that in extreme cases he felt they were at risk.

The Week In Week Out production team spent months with the police, on the streets of Cardiff who were on the lookout for vulnerable children.

As their investigation continued, they found examples of children who should have been in care but instead were on the run at risk and vulnerable.

The council says it is under resourced compared to English authorities but say they are trying to tackle what they admit is a serious problem.

Week In Week Out is screened at 2235 BST on BBC1 Wales.