A North Carolina man posed as a U.S. Marine stationed at Quantico on online dating sites, then threatened women who declined to send him nude or seductive photographs or other images, authorities said Monday.

James M. Johnson, 29, pleaded guilty to cyberstalking and making interstate threats, according to a statement from the office of U.S. Attorney Neil H. MacBride.

The plea was entered in the Alexandria Division of the Eastern District of Virginia, authorities said. Johnson will face maximum sentences of five years for each count at a sentencing scheduled for Nov. 2.

Johnson admitted to setting up dating profiles using a false name, personal information and photos of a Marine — often using “Cuddleman” as his screen name. He contacted at least 11 women in the mid-Atlantic region, urging them to send him photographs or pose in front of an Internet camera.

When they refused, authorities said, he threatened them. The threats, authorities said, at times included sexual assault, killing their children, and the posting of altered photographs of them on pornographic Web sites.