A man accused of impregnating a 10-year-old girl should spend the rest of his life in prison, prosecutors say, even though rape charges don't allow for such a long sentence.

They plan to argue that pregnancy and childbirth for such a young girl is physical harm, the standard needed to seek a life sentence.

A Hamilton County grand jury on Wednesday charged Michael Chaffer, 40, with two counts of rape and one of felonious assault. Chaffer is accused of raping the now 11-year-old girl many times from Sept. 8, 2006, to Nov. 4, 2007.

"You know I have been doing this job probably too long, but every time you think you have seen it all, somebody like Michael Chaffer comes along and kind of clears the deck," said Hamilton County Prosecutor Joe Deters. "This man is a beast who preyed on a 10-year-old."

The girl's mother remains under investigation, Deters said. Part of the investigation concerns whether the woman knew the abuse was happening.

Deters said the girl hid her pregnancy with big shirts. When she complained of stomach pains Nov. 3, she was taken to University Hospital and gave birth to a 4-pound girl the next day.

"When you hear her story, it's very upsetting," Deters said. "It breaks your heart."

The delivery set off an investigation by the Hamilton County Department of Job and Family Services, and DNA testing proved Chaffer is the infant's father, Deters said.

Chaffer is in prison serving a one-year sentence on an unrelated drug charge.

A hearing in the case is set for next week. Prosecutors are seeking to permanently remove the infant from the girl's care because the sixth-grade student is too young to care for the baby.

A message seeking comment was left with Chaffer's lawyer, Michael Tranter.