A teacher accused of having sex with a 16-year-old schoolboy may have abused as many as six underage boys, police say.

Shannon Moser, 37, who was charged with three felony sex crimes, has had it increased to eight over claims she had sex with a 16-year-old boy and another victim aged 14 or younger.

One of the charges brought against Shannon is gross sexual imposition, a class double-A felony crime considered "heinous" enough to merit life behind bars if convicted.

Investigators have discovered that Shannon Moser, whose husband is a pastor at River City Church in Fargo, may have abused as many as six underage boys. The former science teacher has also now been charged with four counts of luring a minor with electronics.

Pastor

Moser allegedly watched "MILF" (Mother I’d Like to F***) porn and had sex with a 16-year-old student in her van along a quiet road, police say. She is said to have sent nude photos to the boy on Snapchat in June for several days before meeting him at a park one evening after school.

Moser, of West Fargo, North Dakota, is said to have taken the boy for a drive in her van, before pulling onto a gravel road and having sex with him. Afterwards, she reportedly told him "No-one can know," according to WSMV.

Moser is then said to have sent more explicit messages to the boy and asked him for more sex, but he refused.

A second boy, aged 15, alleges that Moser had also been sexting him for a year, starting when he was just 14. He said she had sent him videos of her having sex with her husband, although he says he did not have any physical contact with Moser. He came forward five days after her arrest on July 11.

Cops say they found URLs of MILF porn websites after seizing Moser's phone during their initial interview. Personnel records from Liberty Middle School, where Moser began working in fall 2016, include complaints from some students that she was letting kids call her "Kim Kardashian."

A co-worker who saw Moser playing basketball with an eighth-grade boy said: "The interactions appeared to be uncomfortable because of the physical nature of the basketball game and their interactions appeared to cross student/teacher boundaries."

Moser resigned on July 12, the day after her first police interview, and has been freed on bail ahead of a preliminary court hearing on August 23.