Israeli divers on Thursday found a red suitcase containing a small skull, bones and clothes, which police said may belong to a 4-year-old French girl whose grandfather is jailed in the slaying.

An autopsy was under way, but police said they were convinced the body found in the river in Tel Aviv was Rose Pizem, who has been missing since May. The discovery marked a breakthrough in a sordid case that has captured the nation's attention.

"We found the girl's body but it needs to undergo tests so we can be completely sure it's her," Police Commissioner David Cohen told reporters. Avi Nauman, police commander in the Tel Aviv area, told reporters that there was "a terrible stench coming from the suitcase."

The disappearance has been front-page news in Israel for weeks, with Israelis transfixed by images of the innocent auburn-haired child and the romance between her young mother and a man who was her estranged husband's father.

Rose's grandfather, Roni Ron, initially told police he had killed the little girl in a fit of rage and threw a suitcase containing her body into the Yarkon River. But recently, he said he confessed under duress. He and the girl's mother, Marie-Charlotte Renault, have been arrested.

Rose's father, Benjamin Pizem, told Associated Press Television News from his home in suburban Paris that he spoke with Israeli police about the discovery of the remains. They told him they were conducting DNA tests and would let him know the results later Thursday.

"I was shocked when I saw the images on television of the suitcase," he said, adding he had nothing further to say until the body was identified.

The girl's parents lived together in France, where Rose was born. But when the couple went to meet Pizem's father in Israel, Renault fell in love with the grandfather.

Pizem went back to France and took the girl with him, but Renault suspected he abused her and brought her back to Israel, where Renault bore two daughters with Ron.

Although Rose has been missing since May, authorities weren't aware she had disappeared until late July, when Ron's mother wrote a letter to social services.

Police didn't lift a gag order on the case until a month later, and the details that have emerged since then paint a harrowing picture of a lonely, confused and maltreated child.

The case has prompted soul-searching in Israel, where people began questioning how a little girl could disappear without anyone noticing.