TROPHY CLUB -- Police are investigating allegations that a former teacher and coach at Byron Nelson High School had sex with a 16-year-old female student.
The suspect, a 27-year-old history teacher and junior-varsity baseball coach, resigned Wednesday, officials with the Northwest school district said.
Police said the man, who is being investigated on suspicion of sexual assault of a child under 17 and improper relationship between an educator and student, has not been arrested.
The teacher, who was also a football coach at Medlin Middle School, had worked in the district since 2007, spokeswoman Lesley Weaver said.
"In response to allegations of inappropriate behavior ... the school district and campus officials took appropriate action and notified Child Protective Services for further investigation," Weaver said. "The district is cooperating fully with authorities."
Trophy Club police Cmdr. Lee Delk said his department was called Wednesday by district officials.
Delk said Northlake police are investigating the case with Trophy Club police because the alleged assault occurred during spring break at a hotel in Northlake.
Detectives are setting up interviews with the suspect, the girl and her parents, Delk said.
An e-mail statement by Weaver said the teacher was also investigated in October after Northwest and Byron Nelson High School staffers were told about rumors of an inappropriate relationship between the teacher and a female student.
"The school district and campus conducted a thorough investigation and reported the situation to Child Protective Services," Weaver said. "By the end of October, the district concluded the investigation, finding no evidence of illegal or criminal activity. This was consistent with other agency investigations."
Weaver said that after the investigation, school and district officials continued to monitor the teacher until new information was provided to a school staffer Tuesday.