A Riverhead High School student is suing the district and a principal who she claims sexually assaulted her.

Speaking at a news conference Monday, 18-year-old Anastasia Stapon and her attorney say Dr. Charles Regan groomed the student for months for his "shameful sexual intentions."

"I am here to expose this evil, dirty man," Stapon says.

Stapon and attorney John Ray announced Monday a notice to file a $10 million lawsuit against the Riverhead Central School District and Regan, a married father of two.

Regan allegedly sent Stapon pictures and thousands of text messages during April, many of them sexually explicit.

Inside Regan's office, Ray says the principal pulled Stapon by the neck and "shoved his tongue into her mouth." Stepon says Regan held the back of her neck and brought her closer. She says she got out of there as fast as she could.

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Ray says Regan also made death threats to two other students because Regan was jealous of their relationship with Stapon.

Stapon says she considered Regan a father figure, and her parents say they thought of him as a family friend.

The school district says Regan has been reassigned with pay, pending the outcome of an investigation.

Regan and Riverhead police did not respond to requests for comment.