Lawrence police this week announced the arrests of two teenagers accused of sex crimes against children in their family.

A 14-year-old girl and a 15-year-old boy, both of Lawrence, were taken into custody July 6.

The girl was arrested and charged with felony aggravated criminal sodomy and two counts of felony aggravated indecent liberties with a 3-year-old boy.

She was arrested after reportedly having sexual relations with the child in May at a home on the north side of Lawrence, police said. The suspect and victim in the case are related, court records said.

Douglas County prosecutors charged the 15-year-old suspect with two counts of felony aggravated indecent liberties with a child.

Police said they’re investigating alleged sexual relations between the suspect, a 14-year-old girl and an 11-year-old girl, who are all known to each other. The crimes allegedly occurred between 2005 and 2009 at a home on the north side of Lawrence, police said.

Both suspects, who live in the same home, pleaded not guilty to the charges during July 9 arraignment hearings. They were taken to the Douglas County Juvenile Detention Center, where they’re being held pending Aug. 19 court hearings, court records said.