A convicted sex offender fatally choked a young mother in her Park Rapids, Minn., apartment after having sex with her, according to prosecutors.

Harvey D. Leritz, 21, of Menahga, Minn., appeared Wednesday in Hubbard County District Court on a charge of second-degree intentional murder in the death Monday of Kiela G. Knowles, 19, in her apartment in the 100 block of E. 3rd Street. Leritz remains jailed in lieu of $1 million bail, with conditions.

Police say the two recently met online.

Knowles leaves behind a 2-year-old son.

Leritz was sentenced in September in Hubbard County for fourth-degree criminal sexual conduct and received a 10-year stayed sentence for having sex with a teen under 16 years of age.

According to the criminal complaint:

Police called to the apartment in the early morning hours found "an unclothed, unresponsive female with a pillow over her face" who appeared to be deceased.

An investigator learned that Leritz was the last person to be seen with Knowles and saw apartment building surveillance video showing him entering and exiting her residence several times during the previous day.

Police met with Leritz after he arrived at the apartment on the afternoon after Knowles' body was discovered. Leritz admitted to having sex with Knowles then "killing her by choking her for 20 to 30 minutes."