Police excavating the former Jersey children's home at the centre of a major child abuse investigation may have unearthed more human remains.

Lenny Harper, the deputy chief constable of Jersey Police, said a sniffer dog specially trained to find such remains gave a strong reaction to items found at the same site at Haut de la Garenne where part of a child’s skull was discovered on Saturday, February 23.

Mr Harper said they were “possibly pieces of bone”.

His announcement came as the first picture of a "punishment room" at a former children's home at the centre of a major child abuse investigation revealed a haunting message written on the wall.

On a wooden post against the wall of a secret chamber under Haut de la Garenne, in Jersey, was written the message: "I've been bad for years and years." The picture also appears to reveal a large, concrete bath.

Police have excavated one underground chamber at the former home, which until recently been used as a youth hostel, and believe there could be three more.

Mr Harper said officers did not know where the message in the chamber came from. "We have no idea how long it has been there, or who wrote it," he said.

The chamber has been described by victims as a punishment room where they were physically and sexually assaulted and kept in solitary confinement. Police have not confirmed reports that staff at the home would put up to 25 children in freezing water in the bath.

Officers have been searching Haut de la Garenne since forensic teams found a child’s skull in the north west corner of the building on Saturday, February 23, and more than 160 people have since come forward to claim that they were abused while staying there.

The allegations of physical and sexual abuse go back 40 years, and there are 40 suspects in the inquiry.

As the pictures were released, a former volunteer at the home spoke of encountering children who were "frozen with fear," and said she had been met with a "wall of silence" when she tried to raise concerns.

Christine Bowker said that worked at Haut de la Garenne in the early 1970s before leaving due to concerns at the conduct of some of the staff, who she described as "ice cold".

"They had no civil contact with me whatsoever, and watched me very carefully with the children," she said.

"And if the children relaxed at all or responded to my affection, they glared at the children and they glared at me, then the children just went back into their shells."

She told BBC News 24 that she tried to raise concerns about the atmosphere she encountered at the home after leaving, but was obstructed when she tried to do so.

"When I left... and I left in distress and abuse I received from some of the staff... I couldn’t get anybody to listen to the problem," she said.

"Nobody would listen. There was just a wall of silence. I didn’t say anything to the staff because I knew something was going on which I couldn’t quite put my finger on."

Victims have claimed physical and sexual abuse was "rife" at the former home, which was used for orphans and children with behavioural problems.

It has been claimed that the abuse, the majority of which is understood to have taken place in the 1970s and 1980s, involved staff sexually assaulting boys and girls.

Extra support has been brought in to help the growing police inquiry, after more than 70 victims came forward in the last week and an extra 12 detectives started work today.

Giving the latest press conference outside the home this afternoon, Mr Harper said that several unidentified items had been found in searches so far, and that these had been taken away for examination. He added that bones had also been found, but that they were not human.

"It is too early to say what the significance of those (items discovered) are, but we are going to look at those and are sending them away for further examination," he said.

The deputy chief constable added that it would probably be the end of the week until officers reached the second room.

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