A sex offender has been charged with luring after allegedly making plans to have sex with who he thought was a teenage girl.

Timothy Joshua Adam Carnahan, 24, of Bismarck, is charged with felony luring minors by computer and misdemeanor carrying a concealed firearm or weapon. Court documents say he responded Sept. 2 to an undercover Bismarck Police officer's online ad that said "looking for a good time with no strings attached."

The officer presented himself as a 16-year-old girl, court documents say. Carnahan reportedly gave his phone number, and the two exchanged messages over two days.

During the conversations, Carnahan reportedly asked to meet, take his correspondent to his house and "he would be gentle" during sex acts.

Police arrested Carnahan on Saturday night in a parking lot, where the suspect made plans to meet his correspondent. Officers found a large machete in his car, the case's affidavit said. He reportedly admitted to communicating with whom he thought was a teenage girl about having sex.

In 2012, Carnahan was convicted of indecent liberties in the state of Washington's Cowlitz District Court. He is a registered sex offender in North Dakota with an undetermined risk level.

On Tuesday, his bond was set at $7,500. He is to have no contact with anyone younger than 18.

Reach Jack Dura at 701-250-8225 or jack.dura@bismarcktribune.com.