Two children’s milk teeth and further bone fragments have been found at the former Haut de la Garenne children’s home on Jersey.
Further tests will be carried out to establish whether the teeth were from the same child, and how they came to be there.
Police said they could not be sure whether the bone fragments were human or animal and will be sending them to the UK for tests.
Forensic archeologists are examining the third and fourth of cellars uncovered at the home and a pit that was dug and then covered over.
The investigation is focussing on allegations of sexual and physical abuse at the home, which closed in 1986.
Tests on a skull fragment previously recovered at the site have proved inconclusive.