ABERDEEN, S.D.-A 26-year-old Milwaukee, Wis., man who had been visiting and staying with extended family on the Sisseton-Wahpeton reservation in far northeast South Dakota has been sentenced to 45 years in prison for sexually assaulting two girls under the age of 12.

Dashown Raymond Keys, once out of prison, will be on a lifetime of supervised release.

He was found guilty Dec. 7 by a federal jury after a three-day trial in Aberdeen of four counts of aggravated sexual abuse of a child and two counts of abusive sexual contact with a child.

The convictions stem from incidents between Nov. 1, 2013, and Jan. 1, 2016., when Keys repeatedly sexually abused the girls at the home of one of the victims. Keys had moved to South Dakota from Wisconsin to stay with extended family.

While Keys was primarily and repeatedly sexually abusing the daughter of the family he was staying with, he also sexually abused another child, who was a friend of the daughter and who would come over for sleepovers, according to court documents.

The sexual abuse ended when Keys moved back to Wisconsin.

Three days after his departure, the primary victim of his abuse reported it to her mother. The girl said that Keys had threatened to harm members of the family if she said anything about the sexual abuse.

"The United States Attorney's Office remains committed to protecting these most vulnerable victims of society," said U.S. Attorney for South Dakota Ron Parsons in a statement. "I applaud the bravery displayed by these two young victims in coming forward and facing their abuser in a court of law. This was not an easy process for them, and I hope this significant sentence imposed against this vicious criminal helps them in their healing process going forward."

The case was investigated by the FBI and the Sisseton-Wahpeton Tribal Police Department.

Keys was immediately taken into custody.