AUSTIN (KXAN) — A former Manor High School teacher accused of paying a student to have a sexual relationship with him was charged with sexual assault of a child last month.

The 16-year-old junior approached Matthew Burton, 43, when he was her teacher in December 2015, according to a police affidavit. She asked if she could submit extra credit or attend tutoring since she had a failing grade.

The affidavit states she began to spend time studying in his classroom and learned Burton was leaving the high school soon for a job at the University of Texas.

Burton asked for her number, after bringing breakfast to school for her one day, and they started texting and emailing each other. He gave the teenager $200 the week before winter break after she asked for money to pay for a traffic citation.

Their communication stopped just before winter break, but the teen decided to reach out to him in February. Burton said he was in love with her after watching her perform at a school dance. She told Burton she did not feel the same way, according to the affidavit.

Burton also told her he had cancer and wanted to take her on trips, help pay for her college, buy her a car and leave her money when he died.

On April 1, Burton invited the teenager to Lubbock, where he said he was taking a job at Texas Tech University. During the trip, he proposed to her and gave her an engagement ring, saying they would need to be married if she wanted his money.

During a trip to Austin later that month, Burton rented a hotel room at the Fairfield Inn and Suites off Parmer Lane and I-35, where he offered the teen $500 in exchange for sexual contact. Two days later, she declined to meet Burton again, making him upset. “He reminded her of the business agreement, but she continued ignoring him,” the affidavit states.

He offered her $3,000 if she returned to Lubbock for a visit, allegedly telling her he would post inappropriate photos of her on Facebook if she did not. When the teenager went to Lubbock, Burton deleted the photos in front of her.

Returning to Austin, she ignored communication from her former teacher. He then created a Twitter account, with an inappropriate photo of the student, and contacted friends of the student on Twitter. Burton continued to send emails to the student threatening to ruin her life.

On May 9, the victim told her high school dance teacher she had done something for money to help her family out, but now could not get out of the situation.

Burton was arrested in Lubbock on May 20 and transferred to Travis County Jail on May 30. He bonded out on May 31.

The Travis County Sheriff’s Office determined he violated an Emergency Protective Order and issued a warrant for his arrest on Thursday, June 16. He was found and arrested Friday in Austin, Manor police say.

The department said Burton was still tweeting and texting threats directed at the teenager.

The director of communications at Manor ISD says Burton resigned on his own accord in December due to a poor relationship with his academic team and “dissatisfaction with his teaching assignment and working conditions.” The district’s understanding is that the investigation by authorities found no evidence of an inappropriate relationship while he was employed at Manor High School.

Student-teacher relationships increasingly a problem

In May, KXAN reported lawmakers plan to strengthen penalties for student-teacher relationships. Lawmakers were surprised by current laws that make it legally possible for a teacher to date a student of legal age.

It is only against the law when a teacher and student engage in sexual activity and the student is someone within the teacher’s school district. If the student is not of legal age, it’s against the law regardless.

The Texas Education Agency says they expect to see a continued rise in the relationships. Over the past three school years, the TEA says the number of investigations involving inappropriate relationships increased from 141 in 2009-10 to 179 in 2013-14 and 188 in 2014-15.

There are more than five million students in Texas public schools.  According to the TEA, 910 total investigations were opened last school year.