Updated at 3:15 p.m.: Revised to include Taylor ISD statement.

An Austin-area high school teacher and softball coach had sex with a female student about 10 times last year, police say.

Kendall Therese Lucas (Travis County Sheriff's Office)

Kendall Therese Lucas, 25, has been charged with improper relationship between an educator and student. She faces up to 20 years in prison if convicted of the second-degree felony.

According to an arrest-warrant affidavit obtained by the Austin American-Statesman, the principal and a teacher at Taylor High School in Taylor, about 30 miles northeast of Austin, both told police in late March that they had heard from students that Lucas had a sexual relationship with a 17-year-old student.

Police then interviewed two students who said the victim had confided in them about the relationship.

The victim, who was on the varsity softball team, told police that the relationship lasted from March 2016 until the beginning of the summer, the affidavit says.

She said the first time they had sex, she had gone to Lucas' home to watch a movie; the other encounters usually took place in the backseat of Lucas' vehicle, she said.

According to the affidavit, Lucas told police she had at most 10 sexual encounters with the victim and had already discussed the relationship with school officials.

Lucas turned herself in at the Travis County Jail on March 31 and has since been released on bond.

Taylor ISD said in a statement that Lucas had been placed on administrative leave and that the district was cooperating with authorities.

According to the Taylor High School website, she taught business education and was also an assistant volleyball coach.